Language Interaction in Emergent Grammars: Morphology and Word Order in Bilingual Children’S Code-Switching

languages

Article Language Interaction in Emergent Grammars: Morphology and Word Order in Bilingual Children’s Code-Switching

Virve-Anneli Vihman 1,2

1 Institute of Estonian and General Linguistics, University of Tartu, 50090 Tartu, Estonia; [email protected] 2 Department of Language and Linguistics, University of York, York YO10 5DD, UK

Received: 13 February 2018; Accepted: 19 October 2018; Published: 31 October 2018

Abstract: This paper examines the morphological integration of nouns in bilingual children’s code-switching to investigate whether children adhere to constraints posited for adult code-switching. The changing nature of grammars in development makes the Matrix Language Frame a moving target; permeability between languages in bilinguals undermines the concept of a monolingual grammatical frame. The data analysed consist of 630 diary entries with code-switching and structural transfer from two children (aged 2;10–7;2 and 6;6–11;0) bilingual in Estonian and English, languages which differ in morphological richness and the inﬂectional role of stem changes. The data reveal code-switching with late system morphemes, variability in stem selection and word order incongruence. Constituent order is analysed in utterances with and without code-switching, and the frame is shown to draw sometimes on both languages, raising questions about the MLF, which is meant to derive from the grammar of one language. If clauses without code-switched elements display non-standard morpheme order, then there is no reason to expect code-switching to follow a standard order, nor is it reasonable to assume a monolingual target grammar. Complex morphological integration of code-switches and interaction between the two languages are discussed.

Keywords: code-switching; bilingual acquisition; language interaction; MLF; System Morpheme Principle; Morpheme Order Principle

1. Introduction The bilingual practice of code-switching has been shown, over several decades of research, to consist in systematic linguistic behavior, rather than arbitrary or incompetent language usage. Bilinguals make use of their linguistic resources according to socio-pragmatic motivation, following grammatical patterns, although there is disagreement as to how universal the code-switching patterns are, and how to describe the systematicity. Researchers have noted that code-switching, as an online speech phenomenon, can also “afford insight into the psychological reality of boundaries posited by linguists” (Backus 2003). Less research has investigated children’s code-switching, though differences in code-switching between children and adults may help shed light on the validity of proposed models of constraints on code-switching, linguistic development and the cognitive processes underlying speech production. The gradual abstraction of regularities by monolingual children acquiring a language is difﬁcult to assess based on spontaneous production, but can be made evident in the innovative constructions readily found when lexical items from two languages are combined. This paper examines the morphosyntactic integration of nouns in a dataset of two bilingual children’s language usage. Myers-Scotton’s Matrix Language Frame (MLF) and 4M models (Myers-Scotton 2005; Myers-Scotton and Jake 2000a, 2017) provide clear sets of predictions regarding code-switching.

Languages 2018, 3, 40; doi:10.3390/languages3040040 www.mdpi.com/journal/languages Languages 2018, 3, 40 2 of 24

Because the MLF and 4M models have amassed empirical support and are more systematically elaborated than other models of code-switching, these are chosen here as a framework to compare the child data to, but it should be noted that these were not proposed by the authors as descriptions of child language. The child data are placed against a background of expectations for adult code-switching, but child usage is likely to be less consistent in adherence to norms than adult language. However, developments in usage-based language acquisition research and linguistics more broadly suggest that in general, we are in need of more dynamic, probabilistic models to account for variability in usage across individuals and over the life course; models of code-switching need to become more ﬂexible and dynamic in order to account for numerous sources of variability, including typological differences in language pairs and variation in language proﬁles of bilinguals. The critique implicit in this study applies to any code-switching models which base their claims on assumptions of monolingual clausal representations.

1.1. Bilingual Children’s Speech Bilingual development provides a unique window onto processes in cognitive, social, and linguistic development. Much research has been devoted to the question of whether and to what degree the languages of bilingual children interact; the current consensus is that interaction occurs (Argyri and Sorace 2007; Hulk and Müller 2000; Müller and Hulk 2001), but that children are able to separate their languages fairly early (Hoff 2015; Paradis and Genesee 1996). This must also depend to some extent on the degree to which the languages are separated in the community and the input to the child. Bilingual children’s utterances can also shed light on linguistic development more generally. Usually, the knowledge underlying a child’s output is hidden. It is often unclear whether the production of a particular form reflects knowledge of co-occurrences (use of unanalysed forms or phrases taken directly from the input) or generalised, abstract knowledge (analysis of grammatical forms and ability to recreate them in novel contexts). Innovative constructions can show us what abstractions children make and at what point they can be said to be operational. Code-switched utterances offer opportunities for us to investigate how children apply their emerging grammatical systems to novel items during online speech production. However, it is also important to remember that code-switching is characterised by variability, even among adults: Differences are found between individuals, sociolinguistic communities, and language pairs. In children, quantitative and qualitative differences in bilingual language use have been shown to derive from language proficiency (Meisel 2004; Poplack 1980), age of acquisition (Backus 1996; Deuchar et al. 2014), age during observation (Deuchar and Vihman 2005; Meisel 2004; Vihman 1985) and individual differences (Paradis 2011; Vihman 1998). Meisel’s (1994, p. 417) grammatical deficiency hypothesis predicts a U-shaped developmental pattern, with a high proportion of mixes in early language before grammatical maturation (when structural constraints are irrelevant), followed by a decrease when functional categories are learned and the languages are separated, and subsequent increase in code-switching that is more adult-like. Indeed, studies have shown developmental changes in code-switching behaviour, such as a decline in the proportion of “function words” (variously defined) after the earliest multiword utterances (Meisel 1994; Vihman 1985) and a decline in violations of grammatical constraints during the first few years of language use (Paradis et al. 2000); Deuchar and Vihman(2005) found more predicate than argument language mismatches in the first six months of word combinations. Bolonyai(2000), while investigating bilingual children with Hungarian and English, found that the use of both Hungarian and English-influenced structural frames occurred in utterances with and without code-switching, showing language interaction and attrition. The languages included in the present study, English and Estonian, constitute the same pair as those in Vihman’s (1985, 1998) study of code-switching by bilingual siblings. The younger child in that study is “relatively uninhibited in his use of CS from the beginning,” (Vihman 1998, p. 52) and uses a higher proportion of verbs, as well as switched conjunctions and prepositions (cf. Vihman 2016). Languages 2018, 3, 40 3 of 24

The latter are especially interesting in that English uses prepositions, while Estonian has mostly postpositions. In those data, English prepositions are inserted in Estonian clauses postnominally, in line with the MLF model, yet this usage is not commonly encountered in adult code-switching, where adpositions are rarely switched. Vihman also describes switching across morpheme boundaries, including double marking. She appeals to both linguistic and pragmatic maturation to account for code-switching patterns and notes that MLF violations occur only infrequently. She ﬁnds signiﬁcant differences in code-switching styles between the siblings. Differences are also found in the present study, which focusses on the morphosyntactic structure of code-switched utterances.

1.2. Constraints on Code-Switching Although code-switching often occurs intersententially, intraclausal code-switching is the most revealing in terms of linguistic structure and psycholinguistic processing: “It is only in the bilingual clause that the grammars of both languages are in contact” (Myers-Scotton 2005, p. 329). In intraclausal code-switching, the grammars of the two languages confront each other: either the structures are compatible and thus amenable to code-switching, or they are not. If not, then code-switches may be avoided, or else some strategy must be summoned up to resolve incompatibilities. The study of constraints on code-switching addresses both questions: What is required for compatibility, and how is structural incompatibility resolved? Various structural constraints have been proposed and refined to characterise how bilinguals use elements from two languages within a single clause (Matras and Sakel 2007; Myers-Scotton 1993, 2005; Myers-Scotton and Jake 2000a; Pfaff 1979; Poplack 1980; Sankoff and Poplack 1981). The most influential of these, the Matrix Language Frame (MLF) model, posits an asymmetry between the Matrix Language (ML) and the Embedded Language (EL) in structuring the bilingual clause (Myers-Scotton 1993, 2005; Myers-Scotton and Jake 2000a, 2017). According to this model, a single ML can be identified for every utterance, and this ML determines the morphosyntactic structure of the clause. When elements from another language are inserted, they must be integrated into the morphosyntactic ML Frame—the MLF. Importantly, the later-developed 4M model fine-tunes the MLF by distinguishing between four types of morpheme. Two are seen to be activated conceptually, by the speaker’s intentions: Content morphemes and early system morphemes like noun number marking. The other two are said to be activated structurally, by the grammar of the ML: the late system morphemes (Myers-Scotton 2005; Myers-Scotton and Jake 2000a). Bridge morphemes connect two constituents (e.g., of in ‘age of the child’). Late outsider morphemes depend on information external to their own constitutent to determine their form, with prime examples being verb agreement (governed by the subject), object case (governed by the verb) or noun case governed by certain adpositions. The 4M model predicts that late outsider system morphemes only come from the ML (for more detail and empirical evidence for the 4M model, see (Myers-Scotton and Jake 2000a, 2017)). This paper applies to the dataset of bilingual child utterances two fundamental principles proposed in the MLF and 4M models: (1) the System Morpheme Principle (SMP), which predicts that only the ML will contribute late system morphemes indicating grammatical relations within mixed language constituents, and (2) the Morpheme Order Principle (MOP), which says that the linear order of morphemes will follow the ML. Both of these principles rely on the assumption that a ML can be identified, governing the morphosyntactic frame of an utterance. The validity of this assumption will also be addressed in the paper. Various studies have found data which diverge from these constraints (e.g., Backus 2014; de Bot 2004; Zabrodskaja and Verschik 2015), but the constraints have been found in other studies to describe code-switching behaviour well in various contexts (e.g., Deuchar 2006; Deuchar et al. 2007; Myers-Scotton 2005), including studies of children (Bolonyai 2000; Paradis et al. 2000; Vihman 1998). Appealing to a morphosyntactic frame governed by a ML implies at least the following assumptions, which have been contested by critics of the model (Alvarez-Caccamo 1998; Auer and Languages 2018, 3, 40 4 of 24

Muhamedova 2005; Gardner-Chloros 2005; Gardner-Chloros and Edwards 2004; Zabrodskaja 2009): (1) that spoken language can be characterised by a set of grammatical rules, (2) that two languages interacting in code-switching are mentally represented as independent grammars, (3) that one of the languages can always be identified as the ML, (4) that code-switching adheres to abstract rules rather than surface-level structures emerging in the course of production, and (5) that morphosyntactic structure is paramount in determining code-switching behaviour. This paper questions these points, particularly (2) and (4), and returns to them in the discussion. Nevertheless, after decades of research into both grammatical and sociolinguistic aspects of code-switching, the MLF remains the most explicitly articulated model of grammaticality in code-switching. It proposes a clear set of constraints and predictions for evaluating a new dataset, and its falsifiability is also its strength. The SMP and MOP are investigated here through a linguistic analysis of utterances in a dataset of bilingual children’s mixed language usage. The application of the MOP, even more than the SMP, begs the question of what the ML grammar looks like. It has been noted elsewhere that it is not always possible to identify a ML (e.g., Auer and Muhamedova 2005; Gardner-Chloros and Edwards 2004), for various reasons, one being that the bilingual clause may draw its structure from two different languages. Myers-Scotton has allowed for a composite ML, for example, in cases of L1 attrition or matrix language change (turnover) in progress (Bolonyai 2000; Myers-Scotton and Jake 2000a, 2001). More importantly, structural transfer can affect the grammar of the clause, including word order: “Cross-language interactions and competition occur at the level of the grammar as well as the lexicon” (Kroll and Bialystok 2013, p. 510); see also Schmid and Köpke(2017). Curiously, the literature on code-switching and convergence are mostly separate, although the two phenomena are likely to transpire in the same contexts, going hand in hand in bilingual speech, when the languages are both explicitly activated. A growing body of research shows parallel activation for bilinguals—even in monolingual contexts (Kroll et al. 2006; Marian and Spivey 2003; Thierry and Wu 2007). Johanson(2002) has shown that the same processes may underlie code-switching and structural transfer. Although convergence has been associated with attrition or imperfect acquisition, the approach here assumes that structural transfer and code-switching are part of the same process of bilingual language use. Parallel activation, convergence and transfer make the MLF a moving target. If clauses without code-switched elements display non-standard morpheme order, then the question of whether code-switched utterances follow the morpheme order of the ML becomes moot. Hence, in order to probe the MOP, we look at utterances with and without code-switched elements in the children’s data. Children’s code-switching has been found to conform to Myers-Scotton’s constraints in studies which explicitly examined this question (Bolonyai 2000; Paradis et al. 2000; Vihman 1998). Paradis et al. investigated a group of 15 French-English bilinguals aged 2;0–3;6, recorded separately in the context of each of their languages. Out of three constraints investigated in detail, the authors found few violations of the MOP and ML blocking constraint, but much weaker adherence to the SMP, with 18% of code-switched utterances violating it overall. They also found developmental changes, with higher proportions of SMP violations occurring in recordings when the children were aged 2;6–3;0, and fewer violations before and after this. The young French-English bilinguals in their study generally adhered to adult-like structural constraints, implying complex knowledge of how to combine languages during speech production as well as “language-specific syntactic knowledge even during an early period of development where the use of INFL-related morphosyntax is variable in their two languages” (Paradis et al. 2000, p. 259). Bolonyai(2000) examined predictions of the MLF with two more distant languages, spoken by children who are older and have acquired basic morphosyntax (tense, agreement and case morphology) in both languages, as in this study. Her findings upheld the distinctions of the 4M model, although the children used abstract structure drawing on both languages, affecting the MLF and leading to frequent omission of morphemes required in Hungarian. This study focusses on the validity of the SMP and MOP in children’s bilingual usage. Languages 2018, 3, 40 5 of 24

1.3. The Languages Estonian and English are genetically unrelated; English has become a primary contact language in Estonia only recently, through mobility and globalisation in many spheres of life. Contemporary Estonian shows effects of long-term contact with German, including a strong tendency toward V2 word order. English is analytic, whereas Estonian is fusional-agglutinative (Erelt 2009). A combination of postpositions, prepositions, and cases are used in Estonian to signal the adverbial meanings usually encoded by prepositions in English. English signals argument structure primarily through rigid word order, whereas Estonian uses a complex system of morphological case-marking to signal grammatical relations, with flexible, pragmatically sensitive word order, though SVO is most frequent. Adverbial order differs across the two languages. The morphological richness of Estonian can be clearly seen in verb and noun paradigms. Vihman(2016 ) investigates code-switching with verbs, and provides an overview of core verb morphology. This study emphasises nouns, which provide a greater contrast with English. While only pronouns show any case-marking in English, Estonian nouns take fourteen cases, shown in Table1, with a number of differing declensional paradigms, two of which are exemplified (see Blevins 2008). Kaalep(2012) distinguishes seven basic declension classes, with additional subclasses. The first three cases (NOM, GEN, PAR) are known as the grammatical cases; they are also the most frequent (Granlund et al. under review) and vary in form across lexical items: these three are in bold in Table1. The nominative form is the default, citation form and uninflected stem; the genitive form is the inflectional stem used to form the other cases, from inessive onwards. Genitive case always ends in a vowel and does not always take an affix. Hence, a vowel-final nominative needs no affix and may remain unchanged (as emme, in Table1) or undergo stem change to form genitive case. Consonant-final nouns either add a vowel or delete a consonant, and may undergo stem change as well (e.g., kiige, in Table1). Partitive case ends in either a vowel, ‘-t’ or ‘-d’, and may involve stem change. In some classes it is not an affix but only stem-changing morphology that signals case distinctions, as with kiige vs. kiike, ‘swing.GEN’ vs. ‘swing.PAR’(Table1 ), or ‘room’: tuba ‘room.NOM’, toa ‘room.GEN’. It is also crucial that the genitive form of a noun is the stem for all other cases in singular (except partitive), as well as the nominative plural. This ensures attachment of consonant-initial affixes in accordance with phonological rules, without risk of illicit consonant clusters. Note that this also has implications for code-switched nouns. English, too, employs stem changes in many irregular forms of noun plurals (as with past-tense verbs). In English, these irregulars contrast with highly regular affixal forms. In Estonian, the largest declension class, with 37% of noun lemmas in Child-Directed Speech, is a stem-changing noun class, which depends on syllable duration rather than affixes to convey morphological information (Granlund et al. under review). There is no single “default” class, and stem-changing morphology is productive and frequent. This poses a challenge in code-switching, both for speakers integrating non-sequential morphology and for the MLF model, which depends on embedded segments inserted into a ML frame. When a word is fused with its grammatical morphology (e.g., ‘swing’ in Table1, which undergoes stem-internal consonant gradation to differentiate the genitive kiige and partitive kiike), rather than concatenated (e.g., ‘mommy’, emme.GEN–emme-t.PAR), it is not clear what the MLF model predicts: Should the uninflected default stem be selected for insertion, or would either stem be acceptable for insertion and available for ML marking? When code-switchers select a stem-changing lexeme, they inevitably have to decide which stem to select, and how to integrate the stem changes. Although code-switching may be blocked in certain instances, bilingual children often code-switch because of lexical retrieval issues. In cases where code-switching results from a lexical gap, the choice is not whether to insert an EL lexical item or stay with the ML for morphological integrity, but rather how to integrate the EL morphologically (e.g., apply similar stem changes to the EL, despite phonological differences, or make use of bare stems and affixes despite not suiting the phonological requirements for a particular declension class). This is discussed in Section 3.2. Languages 2018, 3, 40 6 of 24

Table 1. Noun case system in Estonian: overview of functions and forms.

CASEFUNCTIONFORMEXAMPLES subject Kiik Emme NOMINATIVE Ø (default stem form) ‘swing’ ‘mommy’ possession, Vowel-final Kiige Emme GENITIVE affected direct object, (±stem change) ‘swing’s’ ‘mommy’s’ PP complement direct object Vowel + stem change (imperfective, negative), Kiike emme-t PARTITIVE OR numeral phrase ‘swing-OBJECT’ ‘mommy-OBJECT’ -t/d complement kiige-s emme-s INESSIVE In -s ‘in the swing’ ‘in mommy’ -sse kiige-sse/kiike emme-sse ILLATIVE Into OR ‘into the swing’ ‘into mommy’ short form (affixal/short form) emme-st kiige-st ELATIVE out of -st ‘from inside ‘from the swing’ mommy’ on top of, kiige-l emme-l ADESSIVE -l experiencer ‘on the swing’ ‘at mommy’ directional kiige-le emme-le ALLATIVE (exterior location), -le ‘onto the swing’ ‘to mommy’ dative/beneficiary kiige-lt emme-lt ABLATIVE Source -lt ‘off of the swing’ ‘from mommy’ kiige-ga emme-ga COMITATIVE Accompaniment -ga ‘with the swing’ ‘with mommy’ kiige-ta emme-ta ABESSIVE Absence -ta ‘without the swing’ ‘without mommy’ kiige-na emme-na ESSIVE State -na ‘as the swing’ ‘as mommy’ kiige-ks emme-ks TRANSLATIVE change of state -ks ‘turning into the ‘becoming swing’ mommy’ kiige-ni emme-ni TERMINATIVE goal, endpoint -ni ‘as far as the swing’ ‘as far as mommy’

Typically developing, monolingual children acquiring Estonian have been found to acquire the complex noun case system quite early and to use it accurately (Argus 2009b, 2015; Hallap et al. 2014). For an overview of acquisition of Estonian, with reference to typological features, see Argus(2009a) . Granlund and colleagues, in a cross-linguistic, experimental study of 3–5-year-old children’s knowledge of nominal case, found that Estonian children made more errors with stem-changing forms than with invariant stems, but still found high overall accuracy, and improvement with age (Granlund et al.).

2. Data and Methodology The present study follows from earlier studies on Estonian-English children’s language usage (Vihman 1985, 1998), in that it consists of a new dual case study of siblings bilingual in Estonian and English. However, the sociolinguistic context and language skills of the children in this study are different from those cited. The children included in the earlier studies by M. Vihman spoke Estonian at home, in an English-dominant community, whereas the present study involves a bilingual home within an Estonian-speaking community, with each parent speaking a different language with the Languages 2018, 3, 40 7 of 24 children. For the majority of the data collection, the family resided in Estonia. A subset of the data is described and analysed in Vihman(2016), which focusses on code-switching of verbs. The family thus follows a ‘one-parent, one-language’ model, with the mother (myself) speaking American English and the father speaking Estonian, but the policy is not strictly enforced. Estonian is the language the parents usually speak with each other, and the main social language outside the home; however, either parent might join a conversation in the other’s language, often using that language. During the period of data collection, intrasentential code-switching appeared in the parents’ language—especially in cases of culturally or situationally specific items, such as terms related to holidays, school, or local landmarks. Impressionistically, however, code-switching was not as frequent in the parents’ speech as in the children’s. Parental code-switching tended to follow the norms of inflectional morphology as predicted by the MLF: EL items usually inflected according to the Matrix Language, particularly with late system morphemes. Unfortunately, we lack objective data on the child-directed speech heard by the children in this study, and more generally, we lack comparable spoken data from adults bilingual in English and Estonian. Recent research has found some variability in the use of English and Estonian in computer-mediated communication (on Facebook, Igav 2013; in blogs, Kask 2016). Most of the studies to date, however, involve native Estonian speakers who make liberal use of L2 English in their writing. The insertion of Estonian words in an English context by adults has not been investigated. For most of the period of data collection, the children were attending full-time day-care or school in Estonian. However, they showed a striking preference for English when speaking with each other. This may be due to the amount of time spent with their mother, or the abundance of English-language entertainment. The difference between speaking Estonian in the United States and speaking a prestigious, global language like English in Estonia is remarkable; the sociolinguistic context is not the subject of this study, but it very likely has an effect on the language of the children. The family moved to England for two years when the children were aged 4;3–6;3 and 7;11–9;111 (following the main data collection period; examples drawn from the UK period are marked as such). Language dominance was not formally tested, but appeared to be balanced throughout the main data collection, with vocabulary differing by contexts of use. According to both children’s teachers’ reports at the time, their linguistic development in Estonian showed no delay due to bilingualism, and language development was judged to be within norms for typically developing children. The data derive from the author’s diary of her children’s speech, from a period when the two sisters, M and K, were aged 6;6–11;0 and 2;10–7;2, respectively, beginning with 17 months of more intensive diary records, at ages 6;6–7;11 and 2;10–4;3 (prior to moving to the UK). Intermittent recordings were made as well, but they involved an overwhelming majority of English-medium play with minimal code-switching and are not included. Note that diary records do not afford data on frequency or the nature of the input, but they allow us to investigate contexts out of reach of other methodology (Deuchar and Quay 2001; Tomasello 1992). Bilingual utterances produced by the children were written down as soon as possible after they were heard. However, the children produced innumerable bilingual utterances, so the diary necessarily represents only a selection, with particular attention to unexpected usage as well as usage representative of the children’s speech during a particular period. The author was not seeking confirmation or contradiction of hypotheses at the time of data collection, but was rather seeking to portray the children’s bilingual usage, which seemed to be highly individual. The dataset includes 630 utterances and dialogue segments, of which 80% come from K, the younger child. Beyond differences in quantity, the data show differences in the children’s code-switching styles. Examples of both code-switching and structural transfer were noted; 421 of K’s 504 utterances, and 69 of M’s 125 utterances involve code-switching (with or without transfer). Yet we cannot make claims about a

1 This notation is used in developmental literature to indicate age: x;y.z = x years, y months, z days. Languages 2018, 3, 40 8 of 24 developmental trajectory based on this: individual differences are great in some areas, these data are somewhat sparse, and the sample is too small to draw conclusions about what drives these differences. The high proportion of examples with Estonian insertions into English utterances reﬂects the bias created by the observer’s role (Labov 1972; Lanza 1997): The utterances most frequently heard and noted came from an English discourse context. The data were coded according to type of bilingual phenomenon, code-switched elements, and indications of structural transfer. For the present analysis, examples were coded for adherence to the SMP and MOP as well as morphological integration.

3. Language Analysis and Results Analysis of the data addresses three issues: (1) code-switching of late system morphemes; (2) incorporation of stem-changing morphology; and (3) morpheme order. The example in (1) conforms neatly to Myers-Scotton’s notion of ‘classic code-switching’, in which one of the participating languages is the sole source of the morphosyntactic frame. Although the content words in the subordinate clause are Estonian, the ML can be identiﬁed as English: English provides all the grammatical morphemes, and the clause itself is embedded in an English-language main clause, during an English-medium conversation. The utterance refers to a semi-formal lesson at day-care; some switched nouns are technical terms, for which the translation equivalent may not be available to the child. Yet the word for ‘fox’, providing the case-bearing element in the compound noun, is a highly familiar noun for Estonian children (it is also used by K at 2;11 in ex. 20).

1. Mother: Why did you get a sticker? M: Because I knew why the (M, 6;8.7) polaar-rebane -’s kõht is valge. Arctic-fox.NOM(EST) -GEN(ENG)2 stomach white

One striking point about (1) is the form of the noun rebane ‘fox.NOM’, inflected with an English possessive affix. In the genitive, this noun undergoes a stem change to rebase rather than receiving an affix. The child learned the phrase polaar-rebase kõht ‘Arctic fox’s stomach’ in Estonian (as attested when repeating the event in Estonian to her father). Yet the NP may not be stored as a multiword unit, and when retrieving the lexemes from Estonian, M reformulated the NP according to the morphosyntactic frame provided by English, removing the Estonian genitive marker to embed an uninflected, nominative noun stem. This demonstrates the power of the MLF model. The question of stem changes is revisited in Section 3.2. First, the next section turns to examples which do not conform as well as (1) to the MLF model’s predictions.

3.1. The System Morpheme Principle The child code-switching data under investigation here show much variability, both within one child’s utterances and across individuals. In example (2), the ML, unarguably English, would leave the noun unmarked (‘winter things’ rather than ‘winter’s things’). If the noun is analysed as a compound, then the first noun in English may be analysed as a stem. Estonian uses genitive case for the first element, hence the genitive inserted form: this can be analysed as an EL island, meaning a phrase-level constituent bearing EL morphology, but placed in a position following ML structural conditions. Yet if the speaker were to seek a stem, then the nominative form talv seems just as amenable to insertion. Stem changes in the paradigm are likely to also affect the storage and retrieval of the forms, making ready-inflected forms more easily retrieved than stems in certain contexts. Particularly for children, with still developing, tenuous grammatical knowledge, switching cases may be more

2 Abbreviations used in glosses: DIM: DIMINUTIVE, ENG: ENGLISH, EST: ESTONIAN, GEN: GENITIVE, IMP: IMPERATIVE, INF: INFINITIVE, LOC: LOCATIVE, NOM: NOMINATIVE, SG: SINGULAR, PAR: PARTITIVE, PL: PLURAL, PROG: PROGRESSIVE. Languages 2018, 3, x FOR PEER REVIEW 8 of 23

the bias created by the observer’s role (Labov 1972; Lanza 1997): The utterances most frequently heard and noted came from an English discourse context. The data were coded according to type of bilingual phenomenon, code‐switched elements, and indications of structural transfer. For the present analysis, examples were coded for adherence to the SMP and MOP as well as morphological integration.

3. Language Analysis and Results Analysis of the data addresses three issues: (1) code‐switching of late system morphemes; (2) incorporation of stem‐changing morphology; and (3) morpheme order. The example in (1) conforms neatly to Myers‐Scotton’s notion of ‘classic code‐switching’, in which one of the participating languages is the sole source of the morphosyntactic frame. Although the content words in the subordinate clause are Estonian, the ML can be identified as English: English provides all the grammatical morphemes, and the clause itself is embedded in an English‐language main clause, during an English‐medium conversation. The utterance refers to a semi‐formal lesson at day‐care; some switched nouns are technical terms, for which the translation equivalent may not be available to the child. Yet the word for ‘fox’, providing the case‐bearing element in the compound noun, is a highly familiar noun for Estonian children (it is also used by K at 2;11 in ex. 20).

1. Mother: Why did you get a sticker? M: Because I knew why the (M, 6;8.7) polaar-rebane ‐’s kõht is valge. Arctic‐fox.NOM(EST) ‐GEN(ENG)2 stomach white

One striking point about (1) is the form of the noun rebane ‘fox.NOM’, inflected with an English possessive affix. In the genitive, this noun undergoes a stem change to rebase rather than receiving an affix. The child learned the phrase polaar-rebase kõht ‘Arctic fox’s stomach’ in Estonian (as attested when repeating the event in Estonian to her father). Yet the NP may not be stored as a multiword unit, and when retrieving the lexemes from Estonian, M reformulated the NP according to the morphosyntactic frame provided by English, removing the Estonian genitive marker to embed an uninflected, nominative noun stem. This demonstrates the power of the MLF model. The question of stem changes is revisited in Section 3.2. First, the next section turns to examples which do not conform as well as (1) to the MLF model’s predictions.

3.1. The System Morpheme Principle The child code‐switching data under investigation here show much variability, both within one child’s utterances and across individuals. In example (2), the ML, unarguably English, would leave the noun unmarked (‘winter things’ rather than ‘winter’s things’). If the noun is analysed as a compound, then the first noun in English may be analysed as a stem. Estonian uses genitive case for the first element, hence the genitive inserted form: this can be analysed as an EL island, meaning a phrase‐level constituent bearing EL morphology, but placed in a position following ML structural conditions. Yet if the speaker were to seek a stem, then the nominative form talv seems just as amenable to insertion. Stem changes in the paradigm are likely to also affect the storage and retrieval Languagesof the forms,2018, 3 ,making 40 ready‐inflected forms more easily retrieved than stems in certain contexts.9 of 24 Particularly for children, with still developing, tenuous grammatical knowledge, switching cases may be more effortful, and inflected forms easier to code‐switch. This example does not flout effortful, and inﬂected forms easier to code-switch. This example does not ﬂout predictions, but predictions, but demonstrates the interaction of languages even in a single embedded lexeme. demonstrates the interaction of languages even in a single embedded lexeme.

Languages2. They 2018 ,need 3, x FOR to putPEER on REVIEW their talv-e things when it’s snowing. (K, 3;5.1)9 of 23 Languages 2018, 3, x FOR PEER REVIEW 9 of 23 winter‐GEN.SG Kask (2016, p. 94) describes examples from Estonian blogs of English affecting L1 Estonian usage Kask (2016, p. 94) describes examples from Estonian blogs of English affecting L1 Estonian usage evenKask in monolingual(2016, p. 94) clauses, describes where examples nominative from Estonian forms are blogs used of with English elements affecting expected L1 Estonian to be in 2even Abbreviations in monolingual used in clauses, glosses: DIMwhere: DIMINUTIVE nominative, ENG: E formsNGLISH are, EST used: ESTONIAN with, GENelements: GENITIVE expected, IMP: IMPERATIVE to be in, usagegenitive even case in monolingualin standard Estonian clauses, wherenoun compounds. nominative formsThe genitive are used inflection with elements on the expected embedded to benoun in genitiveINF: INFINITIVE case in, LOCstandard: LOCATIVE Estonian, NOM: NOMINATIVEnoun compounds., SG: SINGULAR The, genitivePAR: PARTITIVE inflection, PL: PLURAL on the, PROG embedded: PROGRESSIVE noun. genitiveis a system case morpheme, in standard but Estonian it is a noun bridge compounds. late morpheme The genitive in the 4M inﬂection model on (Myers the embedded‐Scotton and noun Jake is is a system morpheme, but it is a bridge late morpheme in the 4M model (Myers‐Scotton and Jake a2000a) system, which morpheme, may come but it from is a bridge either latelanguage. morpheme Late inoutsider the 4M morphemes model (Myers-Scotton maintain the and grammatic Jake 2000aal), 2000a), which may come from either language. Late outsider morphemes maintain the grammatical whichstructure may of come the Matrix from either Language language. and cannot Late outsider be switched. morphemes Our data, maintain however, the contain grammatical code‐switching structure structure of the Matrix Language and cannot be switched. Our data, however, contain code‐switching ofinvolving the Matrix both Language kinds of and late cannot system be morphemes. switched. Our data, however, contain code-switching involving involving both kinds of late system morphemes. both kindsEmbedded of late objects system exhibit morphemes. patterns of marking from either language, with examples of various Embedded objects exhibit patterns of marking from either language, with examples of various strategies:Embedded Objects objects following exhibit ML patterns or EL ofstructure, marking and from utterances either language, with EL with verb examples and object of together various, strategies: Objects following ML or EL structure, and utterances with EL verb and object together, strategies:which can Objects sometimes following be analysed ML or EL as ELstructure, islands and. Object utterances NPs follow withing EL verbthe MLF and objectmay appear together, in which can sometimes be analysed as EL islands. Object NPs following the MLF may appear in whichnominative can sometimes case in an be English analysed MLas utterance EL islands., as in Object (3a–b), NPs or followingcase‐marked the with MLF object may appear case in in an nominative case in an English ML utterance, as in (3a–b), or case‐marked with object case in an nominativeEstonian MLF case (4) in, as an predicted English by ML the utterance, model: as in (3a–b), or case-marked with object case in an Estonian MLF (4), as predicted by the model: Estonian MLF (4), as predicted by the model:

3. a. Do you see the red pilve-d ? (K, 3;11.28) 3. a. Do you see the red pilve-d ? (K, 3;11.28) clouds‐NOM.PL clouds‐NOM.PL

b. Do for me a big hoog , Mommy. (K, 3;4.18) b. Do for me a big hoog , Mommy. (K, 3;4.18) momentum.NOM.SG momentum.NOM.SG ‘Give me a big push, Mommy’ (context: on swing) ‘Give me a big push, Mommy’ (context: on swing)

4. Oota Nana! Pane oma seatbelt‐i peale. (M, 6;7.26) 4. Oota Nana! Pane oma seatbelt‐i peale. (M, 6;7.26) wait Nana put.IMP own seatbelt‐GEN on wait Nana put.IMP own seatbelt‐GEN on ‘Wait, Nana! Put your seatbelt on’ ‘Wait, Nana! Put your seatbelt on’

TheThe plural plural direct direct object object in (3a), in (3a),pilved pilved‘clouds’, ‘clouds’, bears an bears Estonian an Estonian plural marker plural but marker is in nominative but is in The plural direct object in (3a), pilved ‘clouds’, bears an Estonian plural marker but is in case,nominative which would case, which not be would an option not followingbe an option the following verb nägema the‘see’ verb in nägema Estonian ‘see’. The in Estonian clause obeys. The nominative case, which would not be an option following the verb nägema ‘see’ in Estonian. The Englishclause obeys ML structural English ML constraints. structural In constraints. (3b), the utterance In (3b), looksthe utterance like an Englishlooks like MLF an byEnglish most MLF criteria by clause obeys English ML structural constraints. In (3b), the utterance looks like an English MLF by (numbermost criteria of English (number morphemes, of English verb morphemes, inflection), verb but inflection this structure), but is th a directis structure translation is a direct of an translation idiomatic most criteria (number of English morphemes, verb inflection), but this structure is a direct translation expressionof an idiomatic in Estonian expression for pushingin Estonian someone for pushing on a swing, someonetegema on a hoogu swing,‘to tegema make/give hoogu ‘to momentum’. make/give of an idiomatic expression in Estonian for pushing someone on a swing, tegema hoogu ‘to make/give Althoughmomentum’. the directAlthough object the takes direct partitive object take cases partitive in Estonian, case inin thisEstonian, English in framethis English it is in frame unmarked, it is in momentum’. Although the direct object takes partitive case in Estonian, in this English frame it is in nominativeunmarked, case.nominative Hence, case. the object Hence, marking the object follows marking the ML, follows taking the a singular ML, taking indefinite a singular article indefinite despite unmarked, nominative case. Hence, the object marking follows the ML, taking a singular indefinite beingarticle a massdespite noun, being yet a themass structure noun, asyet a the whole structure shows transfer.as a whole In additionshows transfer. to the translated In addition Estonian to the article despite being a mass noun, yet the structure as a whole shows transfer. In addition to the idiom,translated the adverbialEstonian idiom, phrase the ‘for adverbial me’ shows phrase transfer ‘for me’ as well, shows as transfer this construction as well, as requires this construction a dative translated Estonian idiom, the adverbial phrase ‘for me’ shows transfer as well, as this construction pronounrequires (withouta dative pronoun the preposition) (without or the reversed preposition word) orderor reversed in English. word order in English. requires a dative pronoun (without the preposition) or reversed word order in English. InIn (4), (4), the the EnglishEnglish lexical lexical noun noun insertion insertionseatbelt seatbeltis is inflected inflected according according to to one one of of the the mostmost commoncommon In (4), the English lexical noun insertion seatbelt is inflected according to one of the most common EstonianEstonian paradigms, paradigms, with with the vowelthe vowel -i added, ‐i added, a pattern a commonly pattern commonly used with borrowings, used with neologisms,borrowings, Estonian paradigms, with the vowel ‐i added, a pattern commonly used with borrowings, andneologisms, names. The and lexical names. frame The lookslexical Estonian, frame looks yet it Estonian, is more colloquial yet it is more to use colloquial the phrasal to use verb thepane phrasal kinni neologisms, and names. The lexical frame looks Estonian, yet it is more colloquial to use the phrasal ‘putverb closed’ pane kinni (in lieu ‘put of closed’ ‘put on’). (in Hence, lieu of this ‘put example, on’). Hence, too, shows this example, structural too, transfer. shows An structural imperative transfer. verb verb pane kinni ‘put closed’ (in lieu of ‘put on’). Hence, this example, too, shows structural transfer. takesAn imperative a nominative, verb uninflected takes a nominative, object noun uninflected instead of object the case-marked noun instead noun, of the but case this‐marked is a grammatical noun, but An imperative verb takes a nominative, uninflected object noun instead of the case‐marked noun, but phenomenonthis is a grammatical in Estonian phenomenon which tends in to Estonian be acquired which late, tends and so to is be not acquired an unexpected late, and error. so is not an this is a grammatical phenomenon in Estonian which tends to be acquired late, and so is not an unexpectedThe utterances error. in (5) show EL object marking. It is unclear what the SMP would predict here, as unexpected error. EnglishThe lexical utterance objectss in do(5) notshow show EL object case-marking, marking. yetIt is objects unclear do what take the accusative SMP would case, predict as shown here by, as The utterances in (5) show EL object marking. It is unclear what the SMP would predict here, as pronouns.English lexical Both (5a–b)objects employ do not idiomaticshow case verb‐marking, compounds yet objects from Estonian,do take accusative with English case, ‘do’ as translating shown by English lexical objects do not show case‐marking, yet objects do take accusative case, as shown by thepronouns. verb tegema Both‘make/do’ (5a–b) employ and an idiomatic Estonian direct verb objectcompounds in partitive from case. Estonian, These with both Englishhave lexical ‘do’ pronouns. Both (5a–b) employ idiomatic verb compounds from Estonian, with English ‘do’ equivalentstranslating inthe English verb tegema (‘cheat’, ‘make/do’ ‘skip/cut and class’), an Estonian but the generic,direct object or light in partitive verb frame case. is easilyTheseborrowed, both have translating the verb tegema ‘make/do’ and an Estonian direct object in partitive case. These both have aslexical noted equivalents by Myers-Scotton in English and ( Jake‘cheat(2017’, ‘skip/cut) and Toribio class’(),2017 but). the generic, or light verb frame is easily lexical equivalents in English (‘cheat’, ‘skip/cut class’), but the generic, or light verb frame is easily borrowed, as noted by Myers‐Scotton and Jake (2017) and Toribio (2017). borrowed, as noted by Myers‐Scotton and Jake (2017) and Toribio (2017).

5. a. how did you do sohki ? (M, 7;6.5) 5. a. how did you do sohki ? (M, 7;6.5) cheating.PAR cheating.PAR ‘how did you cheat?’ ‘how did you cheat?’

LanguagesLanguages2018 2018, ,3 3,, 40 x FOR PEER REVIEW 102of of 24 2

5. a. how did you do sohki ? (M, 7;6.5) cheating.PAR Languages 2018, 3,‘how x FOR didPEER you REVIEW cheat?’ 10 of 23

b.b. somesome of of the the girls girls did did poppipoppi todaytoday from from dance dance class. class. (M,(M, 7;6.6) 7;6.6) cuttingcutting‐class.-class.PARPAR ‘some‘some of of the the girls girls cut cut dance dance class/didn’t class/didn’t go go to to dance dance class class today’ today’

TheThe code code-switched‐switched objects inin (3–5)(3–5) areare embeddedembedded in in utterances utterances clearly clearly framed framed by by one one language language or orthe 7.the other, othera. aswe, leastas are least in mängi termsin terms- ofn overtofpeitus overt morphemes.- tmorphemes Yet. Yet thewith the dataset the dataset also karu.also includes includes utterances utterances in(K,which in 3;5.10) which the the (non‐finite) verb and object are both inserted. In (6a), there is no light verb, but the phrasal verb (non-ﬁnite) verb andplay object-n are bothhide- inserted.and-seek In-PAR (6a), there is no lightbear. verb,NOM but the phrasal verb tundma tundma ära ‘recognise’ [lit. ‘know away’] is taken wholesale from Estonian, along with the pronominal ära ‘recognise’ ‘We [lit.are ‘knowplaying away’] hide-and is taken-seek wholesalewith the bear.’ from Estonian, along with the pronominal direct directobject object in partitive in partitive case. The case. code-switch The code splits‐switch the splits verb the phrase: verb The phrase lexical: The verb lexical stem, verb along stem with, along direct withobject direct and particle,object and are particle, in Estonian, are in while Estonian, the English while the auxiliary English marks auxiliary tense marks and negation. tense andIn negation Estonian,. b. palun button minu sweater-i-t (K, 3;5.7) Innegation Estonian, is also negation expressed is also periphrastically, expressed periphrastically, yet a past tense negated yet a past verb tense is in negatedpast participial, verb is not in stempast participial,form, as shown pleasenot stem in (6b). form, as shownmy (1 inSG (6b).GEN. ) sweater(ENG)-PAR(EST) (Expected: ‘palun button minu sweater.’) 6. a. Katie‘Please didn’t button tunne my sweater.’ mind äla (=ära). (K, 4;0.3) know.STEM 1SG.PAR PERFECTIVE.PARTICLE

c. there was a big girl and she veereta-s a pall (K, 3;11.24) b. Katie ei tund-nud mind ära. (Monolingual Estonian) SG PST NOM SG NEG know‐PAST .PARTICIPLEroll-3 . 1SG .PAR PERFECTIVEball. ..PARTICLE ‘Katie(Expected didn’t either recognise ‘she veereta me’ -s palli’ OR ‘she veereta- ed a ball’) ‘There was a big girl and she rolled a ball’ TThehe finite finite verb verb provides provides the the clue clue to to the the ML ML ( (e.g.,e.g., KlavansKlavans 1985;1985; MyersMyers-Scotton‐Scotton and and Jake Jake 2017) 2017).. TThe he utterance utterance in in (6 (6a),a), with with the the English English-language‐language auxiliary auxiliary carrying carrying person, person, tense tense and and polarity polarity and and an Estonianan17. Estonian a. lexical lexicalThen verb I verbhave in stem into stemmake form form, the, would wouldjuure be-d. beanalysed analysed as ascon containingtaining an anEL EL island island (non (non-finite ‐(M,finite 6;7.11) verb verb + object+ object + +particle) particle),, but but for for the the fact fact that that the the form form of of the the lexical lexical verb verb follows follows the the EnglishEnglish-language‐language root.NOM.PL(EST) uninflecteduninflected stem stem form form rather rather than than the the participle, participle, as as past past-tense‐tense negation negation in in Estonian Estonian would would require require..

TheThe examples examples shown shown in in (7) (7) are are also also problematic, problematic, with with various various mixtures mixtures of of verb verb and and object object marking marking.. InIn ( (7a),7a), theb. the verb verbIt’s gonna is is marked marked be a cavewith with witha ann affix affix lots ‐of -nn, , which whichplahvatuse seems seems -tod. to make make use use of of the the Estonian Estonian (M,first first 11;0.9) person person singularsingular ending, ending, -n,-n, toto mark mark the the English English progressive progressiveexplosion ‐ing - ing(see-NOM(see V.‐.PL A.Vihman(E VihmanST) 2016 2016, , p. p. 191),191 ) , for further further discussiondiscussion of of this this affix affix).). The The lexical lexical verb verb and and object object look look like like a ann embedded embedded-language ‐language unit, unit, but but they they cancannot not form formc. Thean an EL ELbook island, island, has allif if the the ending töö-lehe is interpreted -d. as English progressive --inging.. T Thehe direct(K, direct 6;6.11) object object nounnoun is is case case-marked‐marked as expectedexpected inin Estonian,Estonian, butbut thisthis markingmarking is is unexpected unexpected if if the the verb verb morphology morphology is work-sheet-NOM.PL(EST) isML ML English. English. Further Further examples examples of verb of verb and object and object morphology morphology from different from different morphosyntactic morphosyntactic systems systemsare (7b), are in which(7b), in the which verb the and verb object and nounobject are noun both are English both English lexemes lexemes yet, notably, yet, notably Estonian, Estonian object objectcase-marking case‐marking is used. is used With. anWith English an English ML, we ML, would we would expect expect null object null object marking, marking, as in “buttonas in “buttonminu minu[my] [my] sweater”. sweater”. InIn ( (7c),7c), wewe dodo find find an an example example of nullof null object object marking, marking, yet hereyet thehere opposite the opposite is expected: is expected The second: The secondclause hasclause an Estonianhas an Estonian verb (with verb an (with Estonian an Estonian voiceless/s/ending) voiceless/s/ending) and Estonian and Est nounonian (with noun Estonian (with Estonianphonology—a phonology clear/l/—but—a clear/ lackingl/—but lacking Estonian Estonian morphology, morphology, as the object as the case object is unmarked). case is unmarked) With an. WithEstonian an Estonian finite verb, finite we verb, would we expect would the expect object the to show object partitive to show case-marking. partitive case If‐marking. Estonian If is Estonian analysed isas analysed the ML as (based the ML on (based the verb on inflection),the verb inflection we would), we expectwould theexpect object the toobject be case-markedto be case‐marked as pall-i as pall‘ball.-i PAR‘ball.’.PAR The’. examplesThe examples in (7) in seem (7) seem to genuinely to genuinely flout flout the model’s the model’s predictions. predictions. Utterances with verb morphology and object marking drawing from different languages are attested7. a. inwe two are dozen mängi examples-n peitus in- thet data, and appearedwith the regularlykaru. in K’s speech between(K, 3;5.10) 3;5 and 4;1 (unfortunately, frequencyplay‐n ishide uninformative‐and‐seek‐PAR with this sort of diarybear. data).NOM The noun data also raise questions about integrating stem changing morphology, discussed in the next section. ‘We are playing hide‐and‐seek with the bear.’

b. palun button minu sweater‐i-t (K, 3;5.7) please my (1SG.GEN) sweater(ENG)‐PAR(EST) (Expected: ‘palun button minu sweater.’) ‘Please button my sweater.’

Languages 2018, 3, x FOR PEER REVIEW 2 of 2

5. a. how did you do sohki ? (M, 7;6.5) cheating.PAR ‘how did you cheat?’

b. some of the girls did poppi today from dance class. (M, 7;6.6) cutting-class.PAR ‘some of the girls cut dance class/didn’t go to dance class today’ Languages 2018, 3, 40 11 of 24

7. a. we are mängi-n peitus-t with the karu. (K, 3;5.10) play-n hide-and-seek-PAR bear.NOM ‘We are playing hide-and-seek with the bear.’ Languages 2018, 3, x FOR PEER REVIEW 11 of 23

b.c. palunthere wasbutton a big girlminu and she veeretasweater-s -i-t a pall (K,(K, 3;5.7) 3;11.24) please my (1SG.GENroll) ‐3sweaterSG.PST (ENG )-PARball.(ENOMST) .SG (Expected:(Expected ‘ paluneither button ‘she veereta minu- ssweater.’) palli’ OR ‘she veereta-ed a ball’) ‘Please‘There button was a bigmy girlsweater.’ and she rolled a ball’

c.Utterances there was with a big verb girl morphology and she veereta and object-s markinga pall drawing from different languages(K, 3;11.24) are attested in two dozen examples in the data,roll- 3andSG.PST appeared regularlyball.NOM in.SG K’s speech between 3;5 and 4;1 (unfortunately, (Expected eitherfrequency ‘she isveereta uninformative-s palli’ OR with ‘she thisveereta sort-ed of a diary ball’) data). The noun data also raise questions ‘There about was integrating a big girl stem and changing she rolled morphology, a ball’ discussed in the next section.

3.2. Accommodating Stem Changes 3.2. Accommodating Stem Changes Most irregular verbs and nouns in English make use of stem changes instead of affixes, and the 17. Mosta. irregularThen I have verbs to andmake nouns the injuure English-d. make use of stem changes instead of affixes,(M, 6;7.11) and the Estonian noun inflectional paradigm centrally involves stem changing morphology (see Section 1.3). Estonian noun inflectional paradigm centrallyroot.NOM involves.PL(EST) stem changing morphology (see Section 1.3). When words with stem changes are code‐switched, decisions must be made regarding the choice of When words with stem changes are code-switched, decisions must be made regarding the choice stem form: This can shed light on how lexical items are selected. Are the embedded words base forms, of stem form: This can shed light on how lexical items are selected. Are the embedded words base selectedb. beforeIt’s gonna any be morphological a cave with lots information of plahvatuse is encoded,-d. or do they involve stem(M, 11;0.9) changes, forms, selected before any morphological information is encoded, or do they involve stem changes, implicating the EL inflectional paradigm? Stemexplosion‐changing-NOM nouns.PL(E mightST) be judged incongruent and implicating the EL inflectional paradigm? Stem-changing nouns might be judged incongruent and resistant to code‐switching when morphology is sequential in one language but fused in the other, resistant to code-switching when morphology is sequential in one language but fused in the other, yet many examples of uninflected, embedded stem forms occur in the data. The utterance in (8a), yet manyc. examplesThe book ofhas uninflected, all the töö embedded-lehe-d. stem forms occur in the data. The utterance (K, 6;6.11) in (8a), repeated from V.‐A. Vihman (2016) uses an EL English verb with ML affix ‘choose-isin’; (8b) has an repeated from Vihman (2016) uses anwork EL- Englishsheet-NOM verb.PL with(EST) ML affix ‘ choose- isin’; (8b) has an English English noun with ML plural affix on an uninflected, base EL stem. noun with ML plural affix on an uninflected, base EL stem.

8. a. Issi kui me käisime arsti‐s (K, 3;9.14) Daddy when we went doctor‐LOC

siis ma choose.i‐si‐n selle sparkly konna. then I choose‐PST‐1SG this.GEN.SG sparkly frog.GEN

‘Daddy, when we went to the doctor’s then I chose this sparkly frog.’

b. We’re going to grow up into naine-s. (K, 3;4.24) woman‐PL(ENG) ‘We’re going to grow up into women.’

InIn these these examples, examples, the the uninflected uninflected base base stem stem is is used used for for the the embedded embedded word. word. In In (8a), (8a), the the context context requiresrequires a a past past tense tense form, form, but but the the embedded embedded lexeme lexeme is ischoose chooserather rather than than the the past past tense tensechose. chose. Choose Choose isis transformed transformed into into an an appropriate, appropriate, vowel-final vowel‐final stem stem with with the the vowel vowel - i‐-,i‐, thus thus allowing allowing the the Estonian Estonian verbverb endings endings to to mark mark past past tense tense and and first first person person singular. singular. Likewise, Likewise, in in (8b), (8b), the the singular singular nominative nominative stemstemnaine naineis is used used instead instead of of the the genitive, genitive,naise- naise,-, which which would would be be used used to to form form the the plural plural in in Estonian Estonian (naise-d(naise-d).). The The MLFMLF modelmodel allows allows that that early early system system morphemes morphemes likelike plural plural markers markers may may come come from from eithereither language language (or (or both, both, Myers-Scotton Myers‐Scotton and and Jake Jake 2000b 2000,b p., p. 1066). 1066) However,. However which, which stem stem form form to useto use is notis not always always clear, clear, sometimes sometimes involving involving variation, variation as, a cans can be be seen seen in in example example (9). (9). Two Two different different plural plural forms,forms, used used successively successively in in (9a) (9a) and and (9b), (9b), show show that thatuse use of of the the base base EL EL form form with with an an ML ML affix affix is is not not always satisfactory, perhaps because it conflicts with the form more frequently occurring in the input, inevitably that in (9b). The use of an embedded noun here is prompted by a lexical gap: this word was learned in school, and M had not encountered the English word ‘workshop’.

9. a. Basically, there are four different töö-tuba-s . (M, 10;1.23) work‐room‐PL(ENG)

Article Language Interaction in Emergent Grammars: Morphology and Word Order in Bilingual Children’s Code-Switching

Virve-Anneli Vihman 1,2

1 Institute of Estonian and General Linguistics, University of Tartu, 50090 Tartu, Estonia; [email protected] 2 Department of Language and Linguistics, University of York, York YO10 5DD, UK

Received: 13 February 2018; Accepted: 19 October 2018; Published: 31 October 2018

Abstract: This paper examines the morphological integration of nouns in bilingual children’s code- switching to investigate whether children adhere to constraints posited for adult code-switching. The changing nature of grammars in development makes the Matrix Language Frame a moving target; permeability between languages in bilinguals undermines the concept of a monolingual grammatical frame. The data analysed consist of 630 diary entries with code-switching and structural transfer from two children (aged 2;10–7;2 and 6;6–11;0) bilingual in Estonian and English, languages which differ in morphological richness and the inflectional role of stem changes. The data reveal code-switching with late system morphemes, variability in stem selection and word order incongruence. Constituent order is analysed in utterances with and without code-switching, and the frame is shown to draw sometimes on both languages, raising questions about the MLF, which is meant to derive from the grammar of one language. If clauses without code-switched elements display non-standard morpheme order, then there is no reason to expect code-switching to follow a standard order, nor is it reasonable to assume a monolingual target grammar. Complex morphological integration of code-switches and interaction between the two languages are discussed.

Keywords: code-switching; bilingual acquisition; language interaction; MLF; System Morpheme

LanguagesPrinciple2018; Morpheme, 3, 40 Order Principle 12 of 24

always satisfactory, perhaps because it conﬂicts with the form more frequently occurring in the input, 1.inevitably Introduction that in (9b). The use of an embedded noun here is prompted by a lexical gap: this word was learned in school, and M had not encountered the English word ‘workshop’.

LanguagesLanguagesLanguages9. a. 20182018 2018Basically,,, 33,, 3xx, FORFORx FOR PEERPEER there PEER REVIEWREVIEW areREVIEW four different töö-tuba-s . (M,1212 10;1.23)ofof 122323 of 23 Languages 2018, 3, x FOR PEER REVIEW 12 of 23 work-room-PL(ENG)

b.b. TööTöö-toa-toa-d -d areareare thesethese these thingsthings things wherewhere where youyou you gogo from fromgo from roomroom room toto roomroom to room andand youandyou canyoucan do docan differentdifferent do different activitiesactivities activities.. . b.b. TööTöö--toa-toatoa--d-d d areare these these things things where where you you go from go from room room to room to room and you and can you do can different do different activities activities. . workworkwork‐‐roomroom‐room‐‐PLPL‐PL(E(E(ESTST)ST) ) workwork‐room-room‐PL-PL(E(ESTST) )

The self‐repetition is informative. The first code‐switched item operates similarly to the verb TheTheTheThe selfself self-repetitionself‐‐repetitionrepetition‐repetition is is is informative. isinformative.informative. informative. The The TheThe first first firstfirst code code code-switchedcode‐switched‐switched‐switched item item item itemoperates operates operatesoperates similarly similarly similarlysimilarly to tothe the to toverb thetheverb verbverb choose in (8a): The uninflected EL base form is selected and inflected with a ML plural affix. However, choosechoosechoosechoose ininin in (8a): (8a): (8a): (8a): T The TheheThe uninflected uninflected uninflecteduninflected EL EL EL ELbase base basebase form form formform is is selected isselectedis selectedselected and and andinflectedand inflected inflectedinflected with with withwitha MLa ML a aplural MLML plural pluralplural affix. affix. affix.However,affix. However, However,However, thethethe wordword word isis is inflectedinflected inflected differentlydifferently differently whenwhen when immediatelyimmediately immediately repeatedrepeated repeated inin (9b)(9b)in (9b),, nownow, now witwit hhwit thetheh ELtheEL stemstemEL stem changechange change thethe word word is is inflected inflected differently differently when when immediately immediately repeated repeated in in (9b) (9b),, now now wit withh the the EL EL stem stem change change and andand ELEL affix.affix. andELand affix.EL EL affix. affix. WhenWhenWhen stemstem stem choicechoice choice isis isnotnot not atat atstake,stake, stake, itit isisit moremoreis more straightforstraightfor straightforwardwardward toto useuseto use aa basebase a base formform form withwith with aa matrixmatrix a matrix WhenWhen stem stem choice choice is isnot not at atstake, stake, it is it more is more straightfor straightforwardward to use to a use base a baseform formwith witha matrix a matrix languagelanguagelanguage affix, affix, affix, affix, as as as as in in in in (10). (10). (10). (10). The TheThe The Estonian Estonian Estonian Estonian nominative nominativenominative nominative plural pluralplural plural morpheme morpheme morpheme morpheme - d -- ddattaches attachesattaches-d attaches to to toa avowel a to vowelvowel a vowel‐final‐‐finalfinal ‐final language affix, as in (10). The Estonian nominative plural morpheme -d attaches to a vowel-final genitivegenitivegenitive form.form.form. form. Here, Here,Here, Here, the thethe the child childchild child at atat 2;11 at2;112;11 2;11 already alreadyalready already employs employsemploys employs stem stemstem stem adaptation adaptationadaptation adaptation by byby adding addingaddingby adding a vowel,aa vowel,vowel, a vowel, -i, --beforeii,, beforebefore -i, before genitive form. Here, the child at 2;11 already employs stem adaptation by adding a vowel, -i, before theLanguagesthethe pluralpluralplural plural 2018 endingendingending ending, 3, x; .doi:. . . FOR PEER REVIEW www.mdpi.com/journal/languages the plural ending.

10. Mul on vaja lõigata picture‐id (K, 2;11.13) 10.10.10. MulMulMul ononon vajavajavaja lõigatalõigatalõigata picturepicturepicture‐id‐id ‐ id (K,(K, 2;11.13) 2;11.13)(K, 2;11.13) to‐me is needed cut.INF picture‐NOM.PL(EST) tototo‐‐meme‐me isis is neededneededneeded cut.cut.cut.INFINF INF picturepicturepicture‐NOM‐NOM‐NOM.PL.PL(E(E.STPLST)(E ) ST ) ‘I need to cut pictures.’ ‘I‘I ‘I needneed need to to tocut cut cut pictures.’ pictures.’ pictures.’

YetYet we we we find find find intra intra intra‐‐speaker‐speakerspeaker variability variability variability, ,, eveneveneven with with with sequential sequential sequential affixes affixes affixes and and and no no no stem stem stem change, change, change, YetYet we we find find intra-speaker intra‐speaker variability, variability, eveneven with with sequential sequential affixes affixes and and no no stem stem change, change, demonstratingdemonstrating an an an open open open choice choice choice between betweenbetween EL EL EL islands islands islands and and and ML ML ML morphological morphological morphological integration integrationintegration. Like.. LikeLike M M Min inin demonstratingdemonstrating an an open open choice choice betweenbetween EL EL islands islands and and ML ML morphological morphological integration. integration. LikeLike M M inin exampleexample (9),(9),(9), K KK also alsoalso makes makesmakes use useuse of ofof both bothboth EL ELEL islands islandsislands and andand ML MLML morphology morphologymorphology affixed affixedaffixed to to toa stem,aa stem,stem, as as asshown shownshown in inin exampleexample (9), (9), K K also also makes makes use use of of both both EL EL islands islands and and ML ML morphology morphology affixed affixed to to a a stem, stem, as as shown shown in in (11(11––13):13): (11–13):(11–13):

11.11. AtAt preschoolpreschoolpreschool the thethe õunaõunaõuna--puu-puupuu‐s‐‐s s startedstartedstarted õitseõitseõitse‐ing‐‐inging 11. At preschool the õuna-puu‐s started õitse‐ing appleappleapple‐tree‐‐treetree‐PL‐‐PLPL(E(E(ENGNGNG) )) bloombloombloom‐PROG‐‐PROGPROG(E((NGEENGNG) )) apple‐tree‐PL(ENG) bloom‐PROG(ENG) andandand thethethe kirsikirsikirsi--puu-puupuu--d-dd too.too.too. and the kirsi-puu-d too. cherrycherrycherry‐‐tree‐treetree‐‐NOM‐NOMNOM.PL..PLPL(E(E(ESTSTST) )) cherry‐tree‐NOM.PL(EST) ‘‘‘AtAtAt preschoolpreschoolpreschool the thethe apple appleapple trees treestrees started startedstarted blooming bloomingblooming and andand the thethe cherry cherrycherry trees treestrees too.’ too.’too.’ (K,(K,(K, 4;0.08) 4;0.08)4;0.08) ‘At preschool the apple trees started blooming and the cherry trees too.’ (K, 4;0.08)

12.12. a.a.a. III found foundfound a aa pinecone pineconepinecone under underunder my mymy seat. seat.seat. In InIn English EnglishEnglish it’s it’sit’s käbikäbikäbi. .. (K,(K,(K, 3;4.22) 3;4.22)3;4.22) 12. a. I found a pinecone under my seat. In English it’s käbi. NOM SG (K, 3;4.22) pinecone.pinecone.pinecone.NOMNOM. ..SGSG s NOM SG III found foundfound a aa käbikäbikäbi . .. SquirrelsSquirrelsSquirrels like likelike käbikäbikäbipinecone.- -.- ss.. . I found a pinecone.käbi. NOM.SG Squirrels likepinecone käbi-‐sPL. (ENG) pinecone.pinecone.NOMNOM..SGSG pineconepinecone‐‐PLPL(E(ENGNG))

pinecone.NOM.SG pinecone‐PL(ENG) b. Two käbi-d. Look, I have two käbi-d. (K, 3;4.28) b.b. TwoTwo käbikäbi--dd.. Look,Look, II havehave twotwo käbikäbi--d.d. (K,(K, 3;4.28)3;4.28) pinecone‐NOM.PL(EST) pinecone‐NOM.PL(EST) b. Two pineconepineconekäbi-d. ‐‐NOMNOM..PLPL(E(ESTST)) Look, I have two pineconepineconekäbi-d.‐‐ NOMNOM..PLPL(E(ESTST)) (K, 3;4.28)

pinecone‐NOM.PL(EST) pinecone‐NOM.PL(EST) 13. There are sajajalgse-d boy‐s and these are sajajalgse-d girl‐d. 13. 13. ThereThere areare sajasajajalgsejalgse--dd boyboy‐‐ss andand thesethese areare sajasajajalgsejalgse--dd girlgirl‐‐d.d. centipede‐PL(EST) boy‐PL(ENG) centipede‐PL(EST) girl‐PL(EST) 13. There are centipedecentipedesajajalgse‐‐PLPL-d(E (ESTST)) boyboyboy‐‐PLPL‐(E(Es NGNG)) and these arecentipede centipedesajajalgse‐‐PLPL-(E(Ed STST)) girlgirl‐‐PLgirlPL(E(E‐STd.ST )) ‘There are centipede boys, and these are centipede girls.’ (K, 3;7.14) ‘There‘There areare centipedecentipedecentipede boys,boys,‐PL andand(EST thesethese) boy areare ‐ centipedecentipedePL(ENG) girls.’girls.’ centipede‐PL(EST(K,(K,) 3;7.14)3;7.14)girl‐ PL (EST)

‘There are centipede boys, and these are centipede girls.’ (K, 3;7.14) WhetherWhether (11) (11) involves involves self self-correction‐correction or simply or simply shows shows arbitrariness arbitrariness in the in choice the choice of ending, of ending, it is it is WhetherWhether (11)(11) involvesinvolves selfself‐‐correctioncorrection oror simplysimply showsshows arbitrarinessarbitrariness inin thethe choicechoice ofof ending,ending, itit isis clearclear that that plural plural marking marking has has been been acquired acquired and and activated activated in both in both languages. languages. The plurals The plurals in example in exampless clearclear thatthat pluralplural markingmarking hashas beenbeen acquiredacquired andand activatedactivated inin bothboth languages.languages. TheThe pluralsplurals inin exampleexampless (12a(12a–b)–b)Whether derive derive from (11) from involvesconversations conversations self‐ correctionon ondifferent different or days.simply days. The shows Thefirstfirst linearbitrariness linein (12a) in (12a) provides in the provides choice a peek of a peekatending, the at theit is (12a(12a––b)b) derivederive fromfrom conversationsconversations onon differentdifferent days.days. TheThe firstfirst lineline inin (12a)(12a) providesprovides aa peekpeek atat thethe metalinguisticclear that plural awareness marking of has the beenbilingual acquired child, and who activated initially inproduces both languages. the compound The plurals lexical in item example s metalinguistic awareness of the bilingual child, who initially produces the compound lexical item pineconemetalinguistic(12a–b) in derive English, awareness from then conversations misof the‐labels bilingual the on Estoniandifferent child, who itemdays. initiall as The Englishy firstproduces line (as shein the (12a) was compound wontprovides to lexical do), a peek and item at the pinecone in English, then mis‐labels the Estonian item as English (as she was wont to do), and continuespineconemetalinguistic in using English, the awareness Estonian then mis ofEL ‐ labelstheitem, bilingual perhaps the Estonian child,due to itemwhoits simpler initiall as English phonologyy produces (as she. The the was source compound wont language to do),lexical for and item continues using the Estonian EL item, perhaps due to its simpler phonology. The source language for pluralcontinuespinecone marking usingin English, varies the Estonian, but then the misEL ML ‐item,labels frame perhaps theis English Estonian due into bothits item simpler (a) as and English phonology (b); in (asEstonian . sheThe source was, plural wont la numeralsnguage to do), for and plural marking varies, but the ML frame is English in both (a) and (b); in Estonian, plural numerals requirepluralcontinues marking partitive using varies singular the Estonian, but nouns the MLEL rather item,frame thanperhaps is English nominative due in to both its plural simpler (a) and (12b). phonology(b) ; Examplein Estonian. The (13), pluralsource again numerals la showsnguage for requirerequire partitivepartitive singular singular nouns nouns rather rather than than nominative nominative plural plural (12b). (12b). Example Example (13) (13) again again shows shows variabilityplural marking within varies a clause:, but Htheere, ML the fr ameadjective is English sajajalgsed in both ‘centipedes (a) and (b) [=; inhundre Estoniand‐legged., pluralPL]’ numerals is variability within a clause: Here, the adjective sajajalgsed ‘centipedes [=hundred‐legged.PL]’ is variabilityrequire partitive within singulara clause: nounsHere, rather the adjective than nominative sajajalgsed plural‘centipedes (12b). [= Examplehundred ‐ (13)legged. againPL]’ shows is variability within a clause: Here, the adjective sajajalgsed ‘centipedes [=hundred‐legged.PL]’ is Languages 2018, 3, 40 13 of 24 metalinguistic awareness of the bilingual child, who initially produces the compound lexical item pinecone in English, then mis-labels the Estonian item as English (as she was wont to do), and continues using the Estonian EL item, perhaps due to its simpler phonology. The source language for plural marking varies, but the ML frame is English in both (a) and (b); in Estonian, plural numerals require partitive singular nouns rather than nominative plural (12b). Example (13) again shows variability Languages 2018, 3, x FOR PEER REVIEW 13 of 23 within a clause: Here, the adjective sajajalgsed ‘centipedes [=hundred-legged.PL]’ is embedded twice LanguagesLanguages 2018 2018, 3, 3x, FORx FOR PEER PEER REVIEW REVIEW 1313 of of23 23 embeddedwith EL plural twice marking. with EL plural The language marking. choiceThe language for the pluralchoice morphemefor the plural on morpheme the ML head on the noun ML (‘boy’, embeddedhead‘girl’)embedded noun contrasts twice(‘boy’ twice ,with with ‘girl’with EL) the ELcontrasts plural adjectiveplural marking. withmarking. in the the Theadjective The first language language NP in (centipede-the choice choicefirst NPfor for PL(centipedethe the(E pluralST plural) boy- ‐morphemePL morpheme(PLEST(E) NGboy )),on‐ PLon thewhereas( EtheNG ML ML)), the headwhereaslanguagehead noun noun the of(‘boy’ language(‘boy’ the, two ‘girl’, ‘girl’ plural of) contrasts )the contrasts markerstwo pluralwith with matches the markers the adjective adjective in matches the in second. in the the in first thefirst The NPsecond NP ‘intrusive’ (centipede (centipede. The ‘intrusive’ EL‐PL‐PL marker(E(STEST) boy )EL boy on ‐markerPL the‐PL(E( secondNGENG o))n,)) , ML whereasthenoun,whereas secondgirl-d the the ML language‘girl language noun-PL(E, ofgirlST of the)’, -thed istwo‘girl two attached ‐pluralPL plural(EST markers to)’, markers ais consonant-final attached matches matches to ina in consonantthe stem,the second second although‐.final The. The ‘intrusive’stem Estonian‘intrusive’, although EL morphophonology EL marker markerEstonian o no n themorphophonologywouldthe second second require ML ML noun a noun vowel-final would, girl, girl- drequire- d‘girl ‘girl stem.‐PL ‐aPL( Evowel(STEST)’,)’, ‐isfinal isattached attached stem. to to a aconsonant consonant‐final‐final stem stem, although, although Estonian Estonian morphophonologymorphophonologyInIn K’s K’s second second utterancewould utterancewould require require in in(14), (14), a vowelathe vowel the embedded‐ embeddedfinal‐final stem stem Estonian. Estonian . noun noun onn onn‘den‘den..SG’ (SGonni’(-onni-dd ‘den.‘den.PL’) takesPL’) takes aa ML MLIn pluralIn pluralK’s K’s second secondaffix, affix, utteranceyet yetutterance this this is in isnot in (14), not (14), attached attachedthe the embedded embedded to tothe the base Estonian baseEstonian form, form, nounalthough noun although onn onn ‘denthis ‘den . thisSGwould.SG’ (’onni would (onni be-d - phonologically‘den.d be‘den. phonologicallyPLPL’) ’)takes takes aacceptableacceptable aML ML plural plural in affix, Englishaffix, English yet yet this ( (onnthisonn is-s,‐ s,isnot akinnot akin attached attached to tolawn-s lawn to -to orsthe orthebun-s base bunbase). -form,s Instead, ).form, Instead, although although the the genitive this genitive this would formwould form isbe be used phonologically isphonologically used as an as embedded an acceptableembeddedbaseacceptable stem, inbase as in Englishin Englishstem Estonian,, as ( onn (inonn ‐ togetherEstonian,s,‐ s, akin akin to withtogether to lawn lawn the-s - MLswithor or bun English bunthe-s ).-MLs ). Instead, plural Instead,English affix the plural the genitive-s genitive. Theaffix same - forms . formThe strategy is same isused used strategy is as illustrated as an an embeddedisinembedded illustrated (15), with base baseinsammu-s (15),stem stem with, as, ‘step.as in samm in Estonian, GENEstonian,u-s+ ‘stepPL together (Etogether.GENNG +)’. PLwith with(ENG the the)’ .ML ML En Englishglish plural plural affix affix -s .- sThe. The same same strategy strategy is isillustrated illustrated in in (15), (15), with with samm sammu-us -‘steps ‘step.GEN.GEN + PL+ PL(E(ENGNG)’.) ’. 14. K: I want to build a onn . (K, 4;4.13) 14. 14. K: K: I wantI want to to build build a a onnden.onn . NOM . .SG (K,(UK(K, 4;4.13) period)4;4.13) Mother: A what? den.den.NOMNOM.SG.SG (UK(UK period) period) Mother:K:Mother: AAA what? what?onn . But when we build onn.i‐ s then you always say ‘clean up it!’ K: K: A A onnden.onn. NOM. .SG But But when when we we build build onn.iden.onn.iGEN‐s‐ s ‐PLthen(EthenNG you) you always always say say ‘clean ‘clean up up it!’ it!’ den.den.NOMNOM.SG.SG den.den.GENGEN‐PL‐PL(E(ENGNG) ) 15. when you all go to sleep, then I will wake up and go with very quiet samm.u‐s to the bathroom. 15. 15. when when you you all all go go to to sleep, sleep, then then I willI will wake wake up up and and go go with with very very quiet quiet samm.u step.samm.uGEN‐s‐ sPL to (Eto theNG the) bathroom bathroom. . ‘...then I will wake up and go, with very quiet steps, to the bathroom.’step. step.GENGEN‐PL‐PL(E(ENGNG(K,) ) 3;4.28) ‘...then‘...then I willI will wake wake up up and and go, go, with with very very quiet quiet steps, steps, to to the the bathroom.’ bathroom.’ (K,(K, 3;4.28) 3;4.28) While the ML is English, the plural stem is adapted according to Estonian morphophonology. MoreoverWhileWhileWhile, the thethe wordML ML is isorderEnglish, English, in thethe the the reportedplural plural plural stem stemspeech stem is isadapted is adapted‘clean adapted upaccording according it!’ according is misrepresented, to to Estonian Estonian to Estonian morphophonology morphophonology though morphophonology. the child. . MoreoverwillMoreover,Moreover have ,heard the, the the word word theword phrase order order order in‘clean in in the the the reportedit reported reportedup’ repeatedly speech speech speech ‘cleanin ‘clean‘clean her upmother’s upup it!’ it!’it!’ is is is misrepresented,input. misrepresented,misrepresented, though thoughthough the thethe child childchild will willhavewill haveIt haveheard is importantheard heard the the phrase the phraseto phrase note ‘clean ‘cleanthat ‘clean itembedded up’it itup’ up’ repeatedly repeatedly repeatedly plural innouns in herin her her mother’sare mother’s mother’s not invariably input.input. input. adapted in the same way. The examplesItIt Itis is isimportant importantimportant in (16) to involveto tonote note note that thatan that embedded uninflected embedded embedded plural (consonantplural plural nouns nouns nouns‐ final)are are not are notstem invariably not invariably with invariably ML adapted pluraladapted adapted affix in in the ,the unlike insame same the thoseway. same way. way. TinTheheT (14he examples examples –examples15), in which in in (16) (16) the involve involve adapted, an an anuninflected voweluninflected uninflected‐final (consonant EL(consonant (consonant-final) stem is‐final) used‐final) stembefore stem stem with withthe with MLsame ML plural ML pluralML plural affixaffix affix., affix,Allunlike, unlike the unlike thosecode those‐ those inswitchedinin (14 (14–15),(14–15)–15) ,nouns in, in inwhich which which in (14 the the– the16)adapted, adapted, have adapted, consonant vowel vowel vowel-final‐final‐final‐final EL EL uninflected,stem stem EL is stem isused used is nominativebefore before used the beforethe same stems. same the ML ML same affix affix. MLAll. All the affix. the code code All‐ ‐ the switched code-switchedswitched nouns nouns in nouns in (14 (14–16) in–16) (14–16)have have consonant consonant have consonant-final‐final‐final uninflected, uninflected, uninflected, nominative nominative nominative stems. stems. stems. 16. a. M: Mommy, Kribu’s [=cat’s name] hand was like this. [bends own hand backward] 16. 16. a. a. M:Mother:M: Mommy,CatsMommy, don’t K haveribu’sKribu’s hands. [=cat’s [=cat’s name] name] hand hand was was like like this. this. [bends [bends own own hand hand backward] backward] Mother:M:Mother: CatsYeah.Cats don’t Onedon’t haveof have her hands. hands.käpp ‐ s was like this. (M, 6;7.12) M: M: Yeah. Yeah. One One of of her her käpppawkäpp‐‐sPL ‐s( ENG) waswas like like this. this. (M, (M, 6;7.12) 6;7.12) paw paw‐PL‐PL(E(NGENG) ) b. It’s creepy. It’s like those metsa -vaim‐s (K, 6;5.3) b. b. It’s It’s creepy. creepy. It’s It’s like like those those metsaforestmetsa-‐vaimspirit-vaim‐s‐‐ PLs (ENG). (K, (K, 6;5.3) 6;5.3) forest forest‐spirit‐spirit‐PL‐PL(E(ENGNG). ) . c. I don’t like Barbies that don’t have tukk‐s, I don’t like how they look. c. c. I don’tI don’t like like Barbies Barbies that that don’t don’t have have tukkbangtukk‐s,‐‐PL s, (ENG) I don’tI don’t like like how how they they look. look.(K, 6;11.22) bangbang‐PL‐PL(E(ENGNG) ) (K,(K, 6;11.22) 6;11.22) From the discourse context in (16a), it is evident that the code‐switch is due to lexical retrieval; the embeddedFromFromFrom the thethe discourse noun discourse in (16b) context context context is from in in (16a), in (16a),a(16a), film, it itis Princess it isevidentis evident evident Mononoke that thatthat the the ,codethe seen code code-switch‐ switchin‐switch Estonian. is isdue due is The to due to lexical noun lexical to lexical inretrieval; retrieval;(16c) retrieval; is thepluralthethe embeddedembedded embedded in American noun noun Englishin in in(16b) (16b) (16b) butis isfrom is singularfrom from a afilm, a film, film,in PrincessEstonian PrincessPrincess Mononoke (likeMononoke Mononoke the, Britishseen, seen, seen in in equivalentEstonian. inEstonian. Estonian. The ‘fringe’): The noun The noun nounitin in is(16c) (16c)given in is (16c) is is plural in American English but singular in Estonian (like the British equivalent ‘fringe’): it is given thepluralplural ML in pluralin American American affix. EnglishEnglish butbut singularsingular inin EstonianEstonian (like(like thethe BritishBritish equivalent ‘fringe’): it it is is given given the the ML plural affix. MLthe pluralExamplesML plural affix. shown affix. in (17) have embedded Estonian plural nouns, with EL stem and affix. Examples shown in (17) have embedded Estonian plural nouns, with EL stem and affix. ExamplesExamples shown in (17) (17) have have embed embeddedded Estonian Estonian plural plural nouns, nouns, with with EL ELstem stem and and affix. affix. 17. a. Then I have to make the juure-d. (M, 6;7.11) 17. 17. a. a. Then Then I haveI have to to make make the the juureroot.juure-NOMd.-d. .PL(EST) (M, (M, 6;7.11) 6;7.11) root.root.NOMNOM .PL.PL(E(ESTST) ) b. It’s gonna be a cave with lots of plahvatuse-d. (M, 11;0.9) b. b. It’s It’s gonna gonna be be a cavea cave with with lots lots of of plahvatuseexplosionplahvatuse-‐d.NOM- d. .PL(EST) (M, (M, 11;0.9) 11;0.9) explosionexplosion‐NOM‐NOM.PL.PL(E(ESTST) ) Languages 2018, 3, x FOR PEER REVIEW 2 of 2

5. a. how did you do sohki ? (M, 7;6.5) cheating.PAR ‘how did you cheat?’

b. some of the girls did poppi today from dance class. (M, 7;6.6) cutting-class.PAR ‘some of the girls cut dance class/didn’t go to dance class today’

7. a. we are mängi-n peitus-t with the karu. (K, 3;5.10) play-n hide-and-seek-PAR bear.NOM ‘We are playing hide-and-seek with the bear.’

b. palun button minu sweater-i-t (K, 3;5.7) please my (1SG.GEN) sweater(ENG)-PAR(EST) (Expected: ‘palun button minu sweater.’) ‘Please button my sweater.’

c. there was a big girl and she veereta-s a pall (K, 3;11.24) roll-3SG.PST ball.NOM.SG (Expected either ‘she veereta-s palli’ OR ‘she veereta-ed a ball’) ‘There was a big girl and she rolled a ball’ Languages 2018, 3, 40 14 of 24

17. a. Then I have to make the juure-d. (M, 6;7.11) root.NOM.PL(EST)

LanguagesLanguages b. 20182018 ,It’s, 33,, xx gonna FORFOR PEERPEER be REVIEWREVIEWa cave with lots of plahvatuse-d. (M, 11;0.9)1414 ofof 2323 explosion-NOM.PL(EST)

c.c. TheThe bookbook hashas allall thethe töötöö--lehelehe--dd.. (K,(K, 6;6.11)6;6.11) c. The book has all the töö-lehe-d. (K, 6;6.11) workwork‐‐sheetsheet‐‐NOMNOM..PLPL(E(ESTST)) work-sheet-NOM.PL(EST)

Although this variation may be entirely open to speaker choice, factors such as complexity of Although this variation may be entirely open to speakerspeaker choice,choice, factors such as complexitycomplexity of morphological formation may contribute to the selection of EL islands like those in (17). The plural morphologicalmorphological formation may contribute to the selection of EL islands like thosethose inin (17).(17). The pluralplural in (c), for instance, involves a stem change, from the nominative stem leht to genitive lehe. The EL in (c),(c), forfor instance,instance, involvesinvolves aa stemstem change,change, fromfrom thethe nominativenominative stemstem lehtleht toto genitivegenitive lehe.lehe. TheThe EL ending may be the most straightforward opt‐out strategy in cases of morphological incongruence, ending may be the mostmost straightforwardstraightforward opt-outopt‐out strategy in cases of morphologicalmorphological incongruence, complexity or uncertainty. complexity or uncertainty. Moreover, in this language pair, plural nouns occurring with numerals and certain quantifiers Moreover, inin thisthis languagelanguage pair,pair, pluralplural nounsnouns occurringoccurring withwith numeralsnumerals andand certaincertain quantiﬁersquantifiers involve a second level of potential incongruence. In Estonian, a numeral greater than one selects a involve a secondsecond levellevel ofof potentialpotential incongruence.incongruence. In Estonian, a numeral greater than one selects a singular noun in partitive case. Hence, when code‐switched nouns appear in numeral phrases, case singular nounnoun inin partitive partitive case. case. Hence, Hence, when when code-switched code‐switched nouns nouns appear appear innumeral in numeral phrases, phrases, case case and and number may be incongruent across the languages. In (9a) above, the switched noun is embedded numberand number may may be incongruent be incongruent across across the languages.the languages. In (9a) In (9a) above, above, the the switched switched noun noun isembedded is embedded in in a numeral phrase, ‘four different töö-tuba-s [work‐room‐PL(ENG)]’. The use of the English‐language ain numeral a numeral phrase, phrase, ‘four ‘four different differenttöö-tuba- töö-tubas-s [work-room-pl(Eng)]’. [work‐room‐PL(ENG)]’. The The use use of of thethe English-languageEnglish‐language plural ending (not partitive singular, as in Estonian) may reflect avoidance of the complicating factor plural endingending (not(not partitivepartitive singular, singular, as as in in Estonian) Estonian) may may reﬂect reflect avoidance avoidance of of the the complicating complicating factor factor of of numeral phrase syntax. In (18), the choice may also be affected by the distinctly un‐English numeralof numeral phrase phrase syntax. syntax In (18),. In the (18), choice the choice may also may be affectedalso be by affected the distinctly by the un-Englishdistinctly un phonology‐English phonology of the stem‐changing noun. The uncertainty and incongruence is clear in the pause and ofphonology the stem-changing of the stem noun.‐changing The uncertainty noun. The anduncertainty incongruence and incongruence is clear in the is pause clear and in the reformulation pause and reformulation with an EL island (numeral and noun). withreformulation an EL island with (numeral an EL island andnoun). (numeral and noun).

18.18. II onlyonly needneed toto dodo twotwo tehetehe‐‐ [pause][pause] onlyonly kakskaks tehettehet [.][.] forfor homework.homework. operationoperation twotwo operationoperation‐‐PARPAR..SGSG(E(ESTST)) (M,(M, 10;2.3)10;2.3)

AA similarsimilarsimilar strategystrategystrategy maymaymay bebebe atatat work workwork in inin (17b, (17b,(17b, ‘lots ‘lots‘lots of ofofplahvatused’, plahvatusedplahvatused’,’,‘explosion ‘explosion‘explosion-NOM--NOMNOM..PL.PLPL’),’’),), whichwhich ininin EstonianEstonian requiresrequire requiress aaa partitive partitive partitive plural plural plural palju paljupalju plahvatusi plahvatusi plahvatusi... The The The bridge bridge bridge morpheme morpheme morpheme ofofof expressesexpressesexpresses semanticsemanticsemantic partitivity,partitivitypartitivity,, butbutbut thisthisthis exampleexampleexample isis betterbetterbetter analysedanalysed asas followingfollowing E EnglishEnglishnglish ML ML structure structure with with an an EL EL island island.island.. InIn (19), (19), (19), the the the opposite opposite opposite choice choice choice is made: is is made: made: The embedded TThehe embedded embedded quantiﬁed quantified quantified noun is in noun noun partitive is is in in singular, partitive partitive imperfectly singular, singular, capturingimperfectimperfectlyly Estonian capturingcapturing morphosyntax: Estoni Estonianan morphosyntax morphosyntax The same phrase:: TThehe in same same Estonian phrase phrase is expressedin in Estonian Estonian with is is expressed expresseda partitive with withplural a a (partitivepartitivepalju punkt-e pluralplural). ((paljupalju punktpunkt--ee).).

19.19. Look,Look, II havehave thatthat muchmuch punktpunkt--i.i. (M,(M, 7;6.6)7;6.6) pointpoint‐‐PARPAR..SGSG((EESTST))

AsAs thethe carefulcareful readerreader maymay notice,notice, thisthis clauseclause isis alsoalso imperfectimperfect inin English,English, wherewhere thethe targettarget wouldwould bebe ‘I‘I havehave thatthat manymanymany points’,points’,points’, ratherratherrather thanthanthan ‘much‘much‘much points.’points.’points.’ TheThe equivalentequivalent EstonianEstonian quantifierquantifierquantifier doesdoes notnot differentiatedifferentiate count countcount from fromfrom mass massmass nouns. nouns.nouns. Hence, Hence,Hence, both bothboth languages languageslanguages feed feedfeed into intointo the thethe grammatical grammaticalgrammatical structure structurestructure of the ofof clausethethe clauseclause constituents. constituents.constituents. ThereThere is is also also somesome evidenceevidence evidence ofof of KK K varyingvarying varying stemstem stem selectselect selectionionion inin incodecode code-switching.‐‐switching.switching. TheThe The exampleexample example inin (20)(20) in (20)involvesinvolves involves aa pluralplural a plural nounnoun noun inin thethe in firstfirst the line, firstline, line,usingusing using aa singularsingular a singular nominativenominative nominative ELEL stemstem EL + stem+ MLML +pluralplural ML plural affix,affix, andand affix, aa andhesitanthesitant a hesitant use use of of use genitive genitive of genitive case case case in in the the in the third third third line, line, line, self self self-repaired‐‐repairedrepaired to to to nominative. nominative. nominative. TT Thehehe requisite requisite bridgebridge morphememorpheme inin EstonianEstonian wouldwould bebe genitivegenitive (=‘fox’s(=‘fox’s baby’)baby’).baby’).. However However,However,, thethe EstonianEstonian nominativenominative isis closestclosest toto thethethe non-case-markednonnon‐‐casecase‐‐markedmarked EnglishEnglish equivalent.equivalent.equivalent.

20.20. K:K: I’mI’m aa rebanerebane .. RebaneRebane‐‐ss don’tdon’t havehave aa bottom.bottom. fox.fox.NOMNOM..SGSG foxfox‐‐PLPL(E(ENGNG)) M:M: Yes,Yes, theythey do!do! K:K: ButBut thisthis isis aa rebaserebase [.][.] rebanerebane baby.baby. (K,(K, 2;11.12)2;11.12) fox.fox.GENGEN..SGSG fox.fox.NOMNOM..SGSG

TheThe examplesexamples providedprovided inin thisthis section,section, illustrativeillustrative ofof nounnoun embeddingembedding inin thethe dataset,dataset, representrepresent considerableconsiderable variation variation when when it it comes comes to to the the question question of of stem stem selection selection and and the the mor morphologicalphological Languages 2018, 3, x FOR PEER REVIEW 14 of 23

c. The book has all the töö-lehe-d. (K, 6;6.11) work‐sheet‐NOM.PL(EST)

Although this variation may be entirely open to speaker choice, factors such as complexity of morphological formation may contribute to the selection of EL islands like those in (17). The plural in (c), for instance, involves a stem change, from the nominative stem leht to genitive lehe. The EL ending may be the most straightforward opt‐out strategy in cases of morphological incongruence, complexity or uncertainty. Moreover, in this language pair, plural nouns occurring with numerals and certain quantifiers involve a second level of potential incongruence. In Estonian, a numeral greater than one selects a singular noun in partitive case. Hence, when code‐switched nouns appear in numeral phrases, case and number may be incongruent across the languages. In (9a) above, the switched noun is embedded in a numeral phrase, ‘four different töö-tuba-s [work‐room‐PL(ENG)]’. The use of the English‐language plural ending (not partitive singular, as in Estonian) may reflect avoidance of the complicating factor of numeral phrase syntax. In (18), the choice may also be affected by the distinctly un‐English phonology of the stem‐changing noun. The uncertainty and incongruence is clear in the pause and reformulation with an EL island (numeral and noun).

18. I only need to do two tehe‐ [pause] only kaks tehet [.] for homework. operation two operation‐PAR.SG(EST) (M, 10;2.3)

A similar strategy may be at work in (17b, ‘lots of plahvatused’, ‘explosion-NOM.PL’), which in Estonian requires a partitive plural palju plahvatusi. The bridge morpheme of expresses semantic partitivity, but this example is better analysed as following English ML structure with an EL island. In (19), the opposite choice is made: The embedded quantified noun is in partitive singular, imperfectly capturing Estonian morphosyntax: The same phrase in Estonian is expressed with a partitive plural (palju punkt-e).

19. Look, I have that much punkt-i. (M, 7;6.6) point‐PAR.SG(EST)

As the careful reader may notice, this clause is also imperfect in English, where the target would be ‘I have that many points’, rather than ‘much points.’ The equivalent Estonian quantifier does not differentiate count from mass nouns. Hence, both languages feed into the grammatical structure of the clause constituents. There is also some evidence of K varying stem selection in code‐switching. The example in (20) involves a plural noun in the first line, using a singular nominative EL stem + ML plural affix, and a hesitant use of genitive case in the third line, self‐repaired to nominative. The requisite bridge morpheme in Estonian would be genitive (=‘fox’s baby’). However, the Estonian nominative is closest Languages 2018, 3, 40 15 of 24 to the non‐case‐marked English equivalent.

20. K: I’m a rebane . Rebane‐s don’t have a bottom. fox.NOM.SG fox‐PL(ENG) M: Yes, they do! K: But this is a rebase [.] rebane baby. (K, 2;11.12) fox.GEN.SG fox.NOM.SG Languages 2018, 3, x FOR PEER REVIEW 15 of 23 TheThe examplesexamples providedprovided inin thisthis section,section, illustrativeillustrative ofof nounnoun embeddingembedding inin thethe dataset,dataset, representrepresent considerableintegrationconsiderable of variation variationnouns. T hey when when are it itnot comes comes necessarily to to the the counter question question‐exam of of ples stem stem to selection selection the model’s and and predictions. the the morphological morphological They integrationillustrate, however, of nouns. how Theythe grammatical are not necessarily systems of counter-examplesboth languages are to crucially the model’s involved predictions. in the Theyproduction illustrate, of an however, utterance, how at all the levels grammatical. This highlights systems the ofneed both for languages a model allowing are crucially for dyna involvedmic inprocesses the production in speech of production an utterance, and atprocessing. all levels. Both This base highlights stems and the inflected need for stems a model are allowingused, and for dynamicmorphology processes may come in speech from the production EL or ML and in either processing. case; the Both children base stems show and occasional inflected uncertainty stems are used,as andto which morphology form is better may come, along from with the sensitivity EL or ML to in morpho either case;logical the mismatches children show between occasional an inflected uncertainty EL asstem to which and ML form affixal is better, morphology. along with We sensitivity cannot directly to morphological compare tmismatcheshese with data between from an adults, inflected but EL stemfurther and research ML affixal would morphology. be welcome We cannot on stem directly selection compare in speech these processing, with data from and adults, on the but factors further researchaffecting wouldmorphological be welcome integration on stem of embedded selection inlanguage speech lexemes processing, in bilingual and on speech the factors. affecting morphological integration of embedded language lexemes in bilingual speech. 3.3. Double Marking 3.3. DoubleOne solution Marking to the stem selection quandary is double marking. Lexical retrieval sometimes accessesOne an solution inflected to EL the form stem, and selection adding quandary ML marking is doubleserves to marking. explicitly Lexical mark integration retrieval sometimes into the accessesMLF and an the inflected intended EL semantic form, and relations adding. MLIn (21), marking metsaserves expresses to explicitly mets ‘forest’ mark + integrationa stem‐changing into the illative case ‘into’. MLF and the intended semantic relations. In (21), metsa expresses mets ‘forest’ + a stem-changing illative case ‘into’. 21. I want to I want go to to metsametsa3 ! 3 ! (K, (K,2;11.9) 2;11.9) go to forest.ILLATIVE(‘into’).SG forest.illative(‘into’).sg The stem change alone alone may may seem seem insufficient insufficient as as a asignal signal of of directionality, directionality, and and the the English English to isto is addedadded for good measure (see (see also also PoplackPoplack et et al. al. ((19891989)) for for similar similar examples examples with with Finnish Finnish-English).‐English). However,However, doubledouble marking is is also also used used in in contexts contexts of of no no stem stem change, change, as as in in (22). (22). Here Here,, the the ML ML prepositionpreposition and EL suffix suffix are are positionally positionally distinct distinct,, again again allowing allowing the the use use of ofdouble double marking marking with with no no structuralstructural conflict.conflict. In In (22a (22a),), case case is is transparent transparent in in the the affix affix,, yet yet do doubleuble marking marking is isemployed employed with with the the EnglishEnglish preposition ‘to’ ‘to’.. The The form form in in (22b) (22b) involves involves a agenitive genitive stem stem and and comitative comitative suffix suffix,, as aswell well as as EnglishEnglish ‘with’:‘with’:

22. a. When I grow up and go to töö-le and daddy’s school, then I can use your scissors. work‐ALLATIVE(‘to’).SG (K, 3;5.1)

b. Where’s that one with the kausi-ga? (K, 3;5.11) bowl‐COMITATIVE(‘with’).SG

As has beenbeen noted previously ((MyersMyers-Scotton‐Scotton 2002;2002; MyersMyers-Scotton‐Scotton and and Jake Jake 20002000aa; ;M. Vihman Vihman 1998 ; Zabrodskaja1998; Zabrodskaja 2009), 2009), double double marking marking may also may occur also withoccur the with morphemes the morphemes stacked stacked in the in same the position,same e.g.,position, with e.g., loan with words loan used words in adult used speechin adult (e.g., speechdžin- (e.g.,s-id džin, < English-s-id, < English plural ‘jean-s’+plural ‘jeanPL‐(Es’+ST PL)).(E DoubleST)). markingDouble marking in child speechin child is speech also noted is also with noted irregular with irregular stems by stemsVihman by( 1998M. Vi, p.hman 67), e.g.,(1998, with p. 67), plural e.g.,feet alsowith receiving plural feet Estonian also receiving plural andEstonian case markingplural and (“ FEETidelecase marking‘to the (“FEETidele FEET’”, at‘to age the 4;3). FEET’”, In the at dataset age under4;3). In consideration, the dataset under this happens consideration, with genitives, this happens as in with (23), genitives, where Estonian as in (23) genitive, whereand Estonian English possessivegenitive and are English both noun-ﬁnal. possessive are both noun‐final.

23. Look, Sandel-i‐’s õde has a telephone in her bag too. Sander‐GEN(EST)‐GEN(ENG) sister.NOM.SG (K, 3;5.0) 3 Because this lexeme involves a change in phonological quantity, not represented orthographically, the gloss does not mark morpheme boundaries. The nominative form is mets; metsa is genitive, and the partitive and (short) illative are mets-a, with a lengthenedWhen the duration. nominative ends in a vowel, many nouns, including names, are syncretic in nominative and genitive case. K attempts to use an EL island (24a), with EL (ø) genitive marking on her sister’s (vowel‐final) name with a code‐switched noun; her older sister corrects her—not with an injunction against code‐switching, but rather on the morphological marking (24b).

3 Because this lexeme involves a change in phonological quantity, not represented orthographically, the gloss does not mark morpheme boundaries. The nominative form is mets; metsa is genitive, and the partitive and (short) illative are mets-a, with a lengthened duration. Languages 2018, 3, x FOR PEER REVIEW 15 of 23

integration of nouns. They are not necessarily counter‐examples to the model’s predictions. They illustrate, however, how the grammatical systems of both languages are crucially involved in the production of an utterance, at all levels. This highlights the need for a model allowing for dynamic processes in speech production and processing. Both base stems and inflected stems are used, and morphology may come from the EL or ML in either case; the children show occasional uncertainty as to which form is better, along with sensitivity to morphological mismatches between an inflected EL stem and ML affixal morphology. We cannot directly compare these with data from adults, but further research would be welcome on stem selection in speech processing, and on the factors affecting morphological integration of embedded language lexemes in bilingual speech.

3.3. Double Marking One solution to the stem selection quandary is double marking. Lexical retrieval sometimes accesses an inflected EL form, and adding ML marking serves to explicitly mark integration into the MLF and the intended semantic relations. In (21), metsa expresses mets ‘forest’ + a stem‐changing illative case ‘into’.

21. I want to go to metsa3 ! (K, 2;11.9) forest.ILLATIVE(‘into’).SG

The stem change alone may seem insufficient as a signal of directionality, and the English to is added for good measure (see also Poplack et al. (1989) for similar examples with Finnish‐English). However, double marking is also used in contexts of no stem change, as in (22). Here, the ML preposition and EL suffix are positionally distinct, again allowing the use of double marking with no structural conflict. In (22a), case is transparent in the affix, yet double marking is employed with the English preposition ‘to’. The form in (22b) involves a genitive stem and comitative suffix, as well as English ‘with’:

22. a. When I grow up and go to töö-le and daddy’s school, then I can use your scissors. work‐ALLATIVE(‘to’).SG (K, 3;5.1)

b. Where’s that one with the kausi-ga? (K, 3;5.11) bowl‐COMITATIVE(‘with’).SG

As has been noted previously (Myers‐Scotton 2002; Myers‐Scotton and Jake 2000a; M. Vihman 1998; Zabrodskaja 2009), double marking may also occur with the morphemes stacked in the same position, e.g., with loan words used in adult speech (e.g., džin-s-id, < English plural ‘jean‐s’+ PL(EST)). Double marking in child speech is also noted with irregular stems by M. Vihman (1998, p. 67), e.g., with plural feet also receiving Estonian plural and case marking (“FEETidele ‘to the FEET’”, at age 4;3). In the dataset under consideration, this happens with genitives, as in (23), where Estonian Languages 2018, 3, 40 16 of 24 genitive and English possessive are both noun‐final.

23. Look, Sandel-i‐’s õde has a telephone in her bag too. Sander‐GEN(EST)‐GEN(ENG) sister.NOM.SG (K, 3;5.0)

LanguagesWhen 2018 the,the 3, x nominative FOR nominative PEER REVIEW ends ends in a in vowel, a vowel, many nouns,many nouns,including including names, are names, syncretic are insyncretic nominative16 of in23 andnominativeLanguages genitive 2018 and,case. 3, x genitive FOR K attemptsPEER case. REVIEW toK attempts use an EL to island use an (24a), EL island with EL(24a) (ø), with genitive EL (ø) marking genitive on marking her sister’s16 ofon 23

(vowel-final)her sister’s (vowel name‐final with) aname code-switched with a code noun;‐switched her older noun sister; her older corrects sister her—not corrects with her— annot injunction with an againstinjunction code-switching, against code‐switching, but rather onbut the rather morphological on the morphological marking (24b). marking (24b). 24. a. K: When is M.. näidend gonna be, for preschool? 24. a. K: When is M... M.. ø = GEN.SG(EST) play.näidendNOM .SG gonna be, for preschool?(K, 6;6.26) 3 Because this lexeme involves a M...change ø = in GEN phonological.SG(EST) quantity, play.NOM not .representedSG orthographically, (K, 6;6.26) the gloss doesb. not M: mark Not morpheme M... boundaries. The nominativenäidend ,form is metsbut; metsa my is genitive,näidend .and the partitive and (short) b. illative M: areNot mets -Ma,M... ‐withø = GEN a lengthened.SG(EST) duration.play.näidendNOM , .SG but my play.näidendNOM. M... ‐’s M‐ø = GENnäidend.SG(EST. ) play. NOM.SG play. NOM M...M...‐GEN‐’s (ENG) play.näidendNOM. (M, 10;2.16) M...‐GEN(ENG) play.NOM (M, 10;2.16) The use of ‘my’ in the initial correction indicates that she is targeting a perceived lack of genitive marking,TheThe use use assuming of of ‘my’ ‘my’ ina in MLF the the initial initial imposing correction correction the morphosyntactic indicates indicates that that she she structure is is targeting targeting on a a theperceived perceived utterance, lack lack ofwhich of genitive genitive her marking,youngermarking, sister assuming assuming fails ato MLF aobserve. MLF imposing imposing Differing the morphosyntactic thechoice morphosyntactic of morphological structure structure form on thes ( e.g., utterance, on thestem utterance, changes which her vs. which younger affixes, her sisterasyounger in Section fails sister to observe.3.2; fails prepositions to observe. Differing vs.D choiceiffering case ofendings, choice morphological of as morphological in ex. forms 21–22; (e.g., formzero stems vs. (e.g., overt changes stem marking, changes vs. affixes, vs.as inaffixes, as 24), in Sectionindicateas in Section 3.2 different; prepositions 3.2; codeprepositions‐switching vs. case vs. endings,strategies. case endings, as It in is ex. likely as 21–22; in ex.that zero 21 this–22; vs. reflects overtzero vs. marking,their overt differing marking, as in 24), status as indicate in with 24), differentrespectindicate to code-switching differentmental representations code‐switching strategies. and strategies. It processing. is likely It that is likely this reflects that this their reflects differing their status differing with status respect with to mentalrespect representations to mental representations and processing. and processing. 4. The Morpheme Order Principle: What ML Grammar? 4.4. The TheVarious Morpheme Morpheme factors Order Order may underlie Principle: Principle: the What What divergences ML ML Grammar? Grammar from predicted? code‐switching patterns discussed in SectVariousVariousion 3.factors Firstfactors and may may foremost, underlie underlie the thethe divergences divergences dataset analysed from from predicted predicted here derives code-switching code from‐switching children’s patterns patterns speech. discussed discussed It in is Sectionimportantin Sect3ion. First to 3 .consider and First foremost, and why foremost, the the datasetexamples the datasetanalysed diverge analysed here from derives predictions here from derives children’s: W fromhether speech. children’s they reflect It is speech. important different It is toconstraintsimportant consider or whyto emerging,consider the examples why not yetthe diverge fully examples acquired from diverge predictions:, grammars. from Whether predictions Secondly, they :Auer W reflecthether and different Muhamedovathey reflect constraints different (2005) or emerging,criticiseconstraints the not MLFor yetemerging, model fully acquired,for not the yet monolingual fully grammars. acquired bias Secondly,, grammars. behind Auer the Secondly, assumption and Muhamedova Auer that and every Muhamedova(2005 clause) criticise draws (2005) the on MLFacriticise structural model the frame forMLF the whichmodel monolingual canfor thebe described monolingual bias behind withthe bias reference assumption behind to the a single thatassumption every language clause that; they every draws cla clauseim on athat structural draws “a neat on frameseparationa structural which between frame can be which describedmatrix can and be with embedded described reference withlanguage to areference single is impossible” language; to a single they language(Auer claim and that; they Muhamedova “a cla neatim separationthat “a(2005 neat, betweenp.separation 52); see matrix also between Gardner and embedded matrix‐Chloros and language 2005;embedded Gardner is impossible” language‐Chloros is ( Auer andimpossible” Edwards and Muhamedova ( Auer2004). and Both( 2005Muhamedova of ,these p. 52); issues see ( also2005 are , Gardner-Chlorosparticularlyp. 52); see also problematic Gardner 2005; Gardner-Chloros ‐whenChloros applied 2005; toGardner children’s and Edwards‐Chloros speech 2004 and. ). Edwards Both of 2004). these issuesBoth of are these particularly issues are problematicparticularlySome of when problematic the literature applied when to on children’s bilingualapplied speech.to children’s children’s language speech. use contrasts adults’ code‐switching, whichSomeSome may of serve of the the literature pragmatic literature on functions bilingualon bilingual like children’s highlightingchildren’s language language informative use contrasts use meanings contrasts adults’ adults’( code-switching,e.g., Myslín code‐ switchingand which Levy , may2015),which serve with may pragmatic ‘code serve‐ mixing’pragmatic functions of children,functions like highlighting saidlike highlightingto derive informative rather informative from meanings pragmatic meanings (e.g., incompetenceMysl (e.g.,ín Myslín and Levy resultingand 2015 Levy), withfrom2015), ‘code-mixing’incomplete with ‘code differentiation‐mixing’ of children, of children, between said to said derive the totwo derive rather language fromrather systems pragmatic from pragmatic before incompetence functional incompetence categories resulting resulting fromhave incompletebeenfrom acquired incomplete differentiation (Meisel differentiation 1989, between 1994). between The the children two the language two studied language systems here systemshave before acquired before functional functionalfunctional categories categories,categories have been haveand acquireditbeen is clear acquired (thatMeisel the (Meisel y1989 are, aware 19941989,). 1994of The using). children The two children languages studied studied here and haveh haveere acquiredhave expectations acquired functional functionaland opinions categories, categories, about and how it and is cleartoit is combine clear that theythat them the are y in aware are code aware of‐switching. using of using two In languagestwo (25), languages M again and and have reacts have expectations to expectations her sister’s and and opinions use opinions of stacked about about howdouble how to combinemarking:to combine them them in code-switching. in code‐switching. In (25), In M (25), again M reactsagain toreacts her sister’s to her use sister’s of stacked use of double stacked marking: double marking: 25. K: Will you put these in Rahel-i‐’s box? [...] (K, 6;6.10) 25. K: Will you put these in RahelRahel‐-GENi‐’s (EST)‐GEN(ENG) box? [...] (K, 6;6.10) M: It’s not Rahel-i-’s. Rahel‐GEN(EST)It’s‐GEN Rahel’s.(ENG) (M, 10;2.0) M: It’s not RahelRahel‐-GENi-’s. (EST)‐GEN(ENG) It’s Rahel’s. (M, 10;2.0) Rahel‐GEN(EST)‐GEN(ENG) The strength of M’s sense of grammaticality is also demonstrated in (26), where she corrects her mother’sThe use usestrength of of morphology morphology of M’s sense in in codeof code-switching. grammaticality‐switching. M’s M’sis alsocorrection corrections demonstrateds demonstrate demonstrate in (26), emerging where emerging she awareness corrects awareness herof ofregularitiesmother’s regularities use and of and recognitionmorphology recognition of in ofdeviations code deviations‐switching. from from them,M’s them, correction as as well well ass as demonstrate rigid rigid adherence adherence emerging to to (unarticulated) awareness of norms.normsregularities. This exampleand recognition indicates of a deviationspreference byfrom M them, for ML as morphological well as rigid adherenceintegration to overover (unarticulated) ELEL islands.islands. norms. This example indicates a preference by M for ML morphological integration over EL islands. 26. Mother: Ok, if you girls want to eat, um, besee-d, then we need to go eat them now. 26. Mother: Ok, if you girls want to eat, um, meringuebesee-d, ‐NOM.thenPL(E STwe) need to go eat them now. M: “ Besee‐s”. meringue ‐NOM.PL(EST) (M, 9;0.0) M: meringue“Besee‐s”.‐ PL(ENG) (UK(M, period) 9;0.0) meringue‐PL(ENG) (UK period)

Languages 2018, 3, x FOR PEER REVIEW 16 of 23

24. a. K: When is M.. näidend gonna be, for preschool? M... ø = GEN.SG(EST) play.NOM.SG (K, 6;6.26)

b. M: Not M... näidend, but my näidend. M‐ø = GEN.SG(EST) play.NOM.SG play.NOM M...‐’s näidend. M...‐GEN(ENG) play.NOM (M, 10;2.16)

The use of ‘my’ in the initial correction indicates that she is targeting a perceived lack of genitive marking, assuming a MLF imposing the morphosyntactic structure on the utterance, which her younger sister fails to observe. Differing choice of morphological forms (e.g., stem changes vs. affixes, as in Section 3.2; prepositions vs. case endings, as in ex. 21–22; zero vs. overt marking, as in 24), indicate different code‐switching strategies. It is likely that this reflects their differing status with respect to mental representations and processing.

4. The Morpheme Order Principle: What ML Grammar? Various factors may underlie the divergences from predicted code‐switching patterns discussed in Section 3. First and foremost, the dataset analysed here derives from children’s speech. It is important to consider why the examples diverge from predictions: Whether they reflect different constraints or emerging, not yet fully acquired, grammars. Secondly, Auer and Muhamedova (2005) criticise the MLF model for the monolingual bias behind the assumption that every clause draws on a structural frame which can be described with reference to a single language; they claim that “a neat separation between matrix and embedded language is impossible” (Auer and Muhamedova (2005, p. 52); see also Gardner‐Chloros 2005; Gardner‐Chloros and Edwards 2004). Both of these issues are particularly problematic when applied to children’s speech. Some of the literature on bilingual children’s language use contrasts adults’ code‐switching, which may serve pragmatic functions like highlighting informative meanings (e.g., Myslín and Levy 2015), with ‘code‐mixing’ of children, said to derive rather from pragmatic incompetence resulting from incomplete differentiation between the two language systems before functional categories have been acquired (Meisel 1989, 1994). The children studied here have acquired functional categories, and it is clear that they are aware of using two languages and have expectations and opinions about how to combine them in code‐switching. In (25), M again reacts to her sister’s use of stacked double marking:

25. K: Will you put these in Rahel-i‐’s box? [...] (K, 6;6.10) Rahel‐GEN(EST)‐GEN(ENG) M: It’s not Rahel-i-’s. It’s Rahel’s. (M, 10;2.0) Rahel‐GEN(EST)‐GEN(ENG)

The strength of M’s sense of grammaticality is also demonstrated in (26), where she corrects her mother’s use of morphology in code‐switching. M’s corrections demonstrate emerging awareness of regularities and recognition of deviations from them, as well as rigid adherence to (unarticulated) Languages 2018, 3, 40 17 of 24 norms. This example indicates a preference by M for ML morphological integration over EL islands.

26. Mother: Ok, if you girls want to eat, um, besee-d, then we need to go eat them now. meringue‐NOM.PL(EST) M: “Besee‐s”. (M, 9;0.0) Languages 2018, 3, x FOR PEER REVIEW 17 of 23 Languages 2018, 3, x FORmeringue PEER REVIEW‐PL(ENG ) (UK period)17 of 23

JudgingJudging appropriate appropriate use use of of code code‐switching‐switching depends depends on on having having models models of of the the grammars grammars of of the the Judging appropriate use of code-switching depends on having models of the grammars of the twotwo languages, languages, as as well well as as having having an an idea idea of of “correct” “correct” code code‐switching‐switching behaviour behaviour. .Yet, Yet, d despiteespite evidence evidence two languages, as well as having an idea of “correct” code-switching behaviour. Yet, despite evidence thatthat the the children children have have knowledge knowledge of of and and access access to to both both systems, systems, the the structures structures underlying underlying speech speech that the children have knowledge of and access to both systems, the structures underlying speech productionproduction may may themselves themselves be be nonstandard, nonstandard, because because of of (a) (a) developmentally developmentally immature immature grammars, grammars, production may themselves be nonstandard, because of (a) developmentally immature grammars, (b)(b) the the mutual mutual influence influence of of the the two two languages, languages, leading leading to to structures structures divergent divergent from from the the assumed assumed (b) the mutual influence of the two languages, leading to structures divergent from the assumed monolingualmonolingual model, model, or or (c) (c) effects effects of of language language interaction interaction in in the the input input the the children children hear, hear, since since both both monolingual model, or (c) effects of language interaction in the input the children hear, since both parentsparents are are fluently fluently bilingual. bilingual. It It is is also also reasonable reasonable to to assume assume that that all all thre threee of of these these factors factors play play a a part, part, parents are fluently bilingual. It is also reasonable to assume that all three of these factors play a part, andand we we cannot cannot tease tease them them apart apart based based on on the the data data presented presented here. here. Yet Yet it it is is impor importanttant to to recognise recognise and we cannot tease them apart based on the data presented here. Yet it is important to recognise thatthat this this fluidity fluidity between between systems systems affects affects not not only only children’s children’s bilingual bilingual language language use, use, but but also also adults’. adults’. that this fluidity between systems affects not only children’s bilingual language use, but also adults’. AssumingAssuming a a monolingual monolingual frame frame for for code code‐switched‐switched utterances, utterances, though though it it may may often often be be descriptively descriptively Assuming a monolingual frame for code-switched utterances, though it may often be descriptively adequate,adequate, is is likely likely to to misrepresent misrepresent the the bilingual bilingual speechspeech production production process, process, which which may may draw draw on on adequate, is likely to misrepresent the bilingual speech production process, which may draw on either eithereither system system or or both. both. system or both. Convergence ConvergenceConvergence While code‐switching and convergence are often examined separately, it is of critical theoretical WhileWhile code-switchingcode‐switching andand convergenceconvergence areare oftenoften examinedexamined separately,separately, itit isis ofof criticalcritical theoreticaltheoretical importanceimportance to to look look at at the the two two phenomena phenomena together. together. FirstFirst, , the the pres presenceence of of convergence convergence makes makes it it importanceespecially clear to look that at languages the two phenomena interact and together. compete First,on a the deeper presence level ofthan convergence the lexicon makes; more itespecially especially clear clear that that languages languages interact interact and and compete compete on on a a deeper deeper level than thethe lexicon; lexicon; moremore importantly,importantly, an an effect effect of of convergence convergence is is to to make make the the grammatica grammatical lframe frame in in question question less less static static——thisthis importantly,inherently problematises an effect of convergence the MOP. Moreover, is to make it the underscores grammatical the frameimportance in question of treating less static—thislanguage as inherentlyinherently problematisesproblematises the the MOP. MOP. Moreover, Moreover, it underscoresit underscores the the importance importance of treatingof treating language language as anas aann inherently inherently dynamic dynamic phenomenon, phenomenon, open open to to creative creative online online construction construction – – especially especially in in bilingual bilingual inherentlyspeech, and dynamic especially phenomenon, as used by open young to creativechildren. online construction – especially in bilingual speech, andspeech, especially and especially as used byas used young by children. young children. InIn addition addition to to the the transfer transfer evidenced evidenced above above, ,e.g., e.g., in in (3b) (3b) and and (5), (5), t hethe dataset dataset includes includes examples examples of lexicalIn addition convergence to the transfer and structural evidenced transfer above, in utterances e.g., in (3b) without and (5), overt the dataset code‐switching includes, examplestoo. These ofof lexicallexical convergenceconvergence andand structuralstructural transfertransfer inin utterancesutterances withoutwithout overtovert code-switching,code‐switching, too.too. TheseThese cancan be be illustrated illustrated with with choice choice of of prepositions prepositions (27 (27aa––bb),), adverbial adverbial order order (28 (28aa––cc),), and and part part‐of‐of‐speech‐speech canflexibility be illustrated (29). with choice of prepositions (27a–b), adverbial order (28a–c), and part-of-speech flexibilityflexibility (29).(29).

27.27. a.a. PalunPalun vaadavaada-ke-ke minuminu loomadeloomade pärastpärast (M,(M, 6;6.1) 6;6.1) please look‐IMP.PL my animal.PL.GEN after please look‐IMP.PL my animal.PL.GEN after

b.b. They’reThey’re so so yummy... yummy... and and they’re they’re with with sugar! sugar! (M,(M, 7;11.3) 7;11.3) (intended:(intended: ‘they ‘they have have sugar sugar on on them’) them’) << Est: Est: nad nad on on suhkruga suhkruga (koos) (koos) ‘they ‘they are are (together) (together) with with sugar’ sugar’

28.28. a.a. I’llI’ll take take this this downstairs downstairs along along. . (M,(M, 6;7.28) 6;7.28) (standard:(standard: ‘I’ll ‘I’ll take take this this along along downstairs’) downstairs’)

b.b. I Ihave have to to open open it it always always because because it it goes goes so so much much times times broken. broken. (M,(M, 7;2.9) 7;2.9) (standard:(standard: ‘I ‘I always always have have to to open open it it because because it it gets gets broken broken so so often.’) often.’)

c.c. WhatWhat do do you you else else like? like? (M,(M, 8;1.28) 8;1.28) (standard:(standard: ‘What ‘What else else do do you you like?’) like?’) (UK(UK period) period)

29.29. OhOh my my gosh, gosh, I’ve I’ve got got two two perfects perfects. .(=perfect (=perfect waffles waffles with with no no holes) holes) (M,(M, 10;3.29) 10;3.29)

TheThe MOP MOP posits posits that that morpheme morpheme order order within within the the bilingual bilingual clause clause comes comes from from only only one one language, language, identifiedidentified as as the the ML. ML. Because Because code code‐switching‐switching research research focusses focusses on on bilingual bilingual utterances, utterances, it it does does not not alwaysalways compare compare code code‐switched‐switched utterances utterances with with singlesingle‐language‐language (m (monolingual)onolingual) utterancesutterances to to test test Languages 2018, 3, x FOR PEER REVIEW 17 of 23

Judging appropriate use of code‐switching depends on having models of the grammars of the two languages, as well as having an idea of “correct” code‐switching behaviour. Yet, despite evidence that the children have knowledge of and access to both systems, the structures underlying speech production may themselves be nonstandard, because of (a) developmentally immature grammars, (b) the mutual influence of the two languages, leading to structures divergent from the assumed monolingual model, or (c) effects of language interaction in the input the children hear, since both parents are fluently bilingual. It is also reasonable to assume that all three of these factors play a part, and we cannot tease them apart based on the data presented here. Yet it is important to recognise that this fluidity between systems affects not only children’s bilingual language use, but also adults’. Assuming a monolingual frame for code‐switched utterances, though it may often be descriptively adequate, is likely to misrepresent the bilingual speech production process, which may draw on either system or both.

Convergence While code‐switching and convergence are often examined separately, it is of critical theoretical importance to look at the two phenomena together. First, the presence of convergence makes it especially clear that languages interact and compete on a deeper level than the lexicon; more importantly, an effect of convergence is to make the grammatical frame in question less static—this inherently problematises the MOP. Moreover, it underscores the importance of treating language as an inherently dynamic phenomenon, open to creative online construction – especially in bilingual speech, and especially as used by young children. In addition to the transfer evidenced above, e.g., in (3b) and (5), the dataset includes examples of lexical convergence and structural transfer in utterances without overt code‐switching, too. These can be illustrated with choice of prepositions (27a–b), adverbial order (28a–c), and part‐of‐speech flexibility (29).

27. a. Palun vaada-ke minu loomade pärast (M, 6;6.1) please look‐IMP.PL my animal.PL.GEN after

b. They’re so yummy... and they’re with sugar! (M, 7;11.3) (intended: ‘they have sugar on them’) < Est: nad on suhkruga (koos) ‘they are (together) with sugar’

28. a. I’ll take this downstairs along. (M, 6;7.28) (standard: ‘I’ll take this along downstairs’)

b. I have to open it always because it goes so much times broken. (M, 7;2.9) (standard: ‘I always have to open it because it gets broken so often.’)

c. What do you else like? (M, 8;1.28) Languages 2018(standard:, 3, 40 ‘What else do you like?’) (UK period)18 of 24

29. Oh my gosh, I’ve got two perfects. (=perfect waffles with no holes) (M, 10;3.29)

Languages 2018, 3, x FOR PEER REVIEW 18 of 23 TheThe MOPMOP positsposits thatthat morpheme order within the bilingual clause comes from only one language, identifiedwhetheridentified this asas theassumptionthe ML.ML. BecauseBecause is valid code-switchingcode—in‐switching fact, monolingual researchresearch focussesfocusses utterances onon may bilingualbilingual be difficult utterances,utterances, to find itit doesdoesin some notnot alwayscontexts.always compare compare For bilingual code-switched code ‐children,switched we utterances utterances cannot assume with with single-languagesingle that‐ languagetheir utterances (monolingual) (monolingual) are framed utterances according to to test test a whethergrammar this equivalent assumption to that is valid—inof either fact,target monolingual language. In utterances the dataset, may we be find difficult code‐ toswitching find in somewith contexts.word order For which bilingual does children, not follow we the cannot ML, assumesuch as that(30). theirThis utterancesis related to are what framed Myers according‐Scotton tohas a grammarcalled a composite equivalent frame, to that resulting of either targetfrom language.low proficiency In the dataset,or attrition: we find “when code-switching speakers do with not wordhave orderfull access which todoes the grammatical not follow the frame ML, suchof the as intended (30). This ML, is related part of to the what abstract Myers-Scotton structure comes has called from a compositeone variety frame, and part resulting from another” from low (Myers proficiency‐Scotton or and attrition: Jake 2000b, “when p. speakers 2). Yet the do languages not have may full access affect toeach the other, grammatical and speakers frame may of the produce intended blended ML, partor composite of the abstract frames structure, even if they comes have from access one varietyto both andgrammars. part from another” (Myers-Scotton and Jake 2000b, p. 2). Yet the languages may affect each other, and speakers may produce blended or composite frames, even if they have access to both grammars. 30. Mommy, vihmaussi-kese-d eat birds! (K, 2;11.21) 30. Mommy, vihmaussi-kese-dearthworms‐DIM‐NOM.PL4 eat birds! (K, 2;11.21) 4 Intended: ‘Birdsearthworms- eat earthworms.’DIM-NOM.PL Intended: ‘Birds eat earthworms.’

The English ML utterance in in (30) (30) is is awkward from from the the point point of of view view of of the the MLF MLF and and the the MOP. MOP. However, this constituent order is no more expected if wewe looklook toto ELEL wordword order.order. Estonian word order is ﬂexible,flexible, but corpus analyses have shown that OVS order with twotwo overtovert nominals,nominals, while acceptable,acceptable, is rare ((LindströmLindström 20042004).). Moreover, OVS is more likely to occur with a light, pronominal object than a marked, focussed, multisyllabic one. However, when we look at the language used by K in (31), we ﬁndfind that she has a liberalliberal approach to constituent order. Whereas M’s examples in (28) show non-standardnon‐standard adverb order, thethe utterancesutterances inin (31)(31) concernconcern thethe corecore argumentsarguments ofof thethe clause.clause.

31. a. [Context: looking at picture cards and labelling them.] Banana is it! Drum is it! (K, 3;0.2) (standard: ‘This is a banana. This is a drum’)

b. I do want a cake to make. (K, 3;0.8) (standard: ‘I do want to make a cake’)

c. Mr. Hoppy is eating his flies now because frogs like flies to catch. (K, 4;4.20) (standard: ‘...frogs like to catch flies’) (UK period)

d. My turn is! (K, 3;0.5) (standard: ‘It’s my turn.’)

e. Very beautiful is that table now! (K, 3;4.4) (standard: ‘That table is very beautiful now.’)

Hence, utterancesutterances using lexemes from a single language language,, with non non-standard‐standard word order order,, can be found in both children’s speech. An example from M with non-standardnon‐standard order of core arguments is given in (32):

32. [Context: Dividing chocolates among four family members, but father is not present.] 4 PluralCan objects we inchoose Estonian one perfective more? clauses Let’s takepretend nominative that case;this hence,one chose the lack Daddy of object-marking. in this example does not disentangle(standard: the intended ‘Let’s pretend argument structurethat Daddy of this chose utterance. this one.’ (M, 7;8.24)

All of these can be analysed as examples of structural transfer, as the translation equivalents are grammatical in Estonian. Examples of untargetlike word order in “monolingual” utterances (with lexemes from one language) puts the code‐switched utterances, as in (33), in a new light:

4 Plural objects in Estonian perfective clauses take nominative case; hence, the lack of object‐marking in this example does not disentangle the intended argument structure of this utterance. Languages 2018, 3, x FOR PEER REVIEW 18 of 23

whether this assumption is valid—in fact, monolingual utterances may be difficult to find in some contexts. For bilingual children, we cannot assume that their utterances are framed according to a grammar equivalent to that of either target language. In the dataset, we find code‐switching with word order which does not follow the ML, such as (30). This is related to what Myers‐Scotton has called a composite frame, resulting from low proficiency or attrition: “when speakers do not have full access to the grammatical frame of the intended ML, part of the abstract structure comes from one variety and part from another” (Myers‐Scotton and Jake 2000b, p. 2). Yet the languages may affect each other, and speakers may produce blended or composite frames, even if they have access to both grammars.

30. Mommy, vihmaussi-kese-d eat birds! (K, 2;11.21) earthworms‐DIM‐NOM.PL4 Intended: ‘Birds eat earthworms.’

The English ML utterance in (30) is awkward from the point of view of the MLF and the MOP. However, this constituent order is no more expected if we look to EL word order. Estonian word order is flexible, but corpus analyses have shown that OVS order with two overt nominals, while acceptable, is rare (Lindström 2004). Moreover, OVS is more likely to occur with a light, pronominal object than a marked, focussed, multisyllabic one. However, when we look at the language used by K in (31), we find that she has a liberal approach to constituent order. Whereas M’s examples in (28) show non‐standard adverb order, the utterances in (31) concern the core arguments of the clause.

31. a. [Context: looking at picture cards and labelling them.] Banana is it! Drum is it! (K, 3;0.2) (standard: ‘This is a banana. This is a drum’)

b. I do want a cake to make. (K, 3;0.8) (standard: ‘I do want to make a cake’)

c. Mr. Hoppy is eating his flies now because frogs like flies to catch. (K, 4;4.20) (standard: ‘...frogs like to catch flies’) (UK period)

d. My turn is! (K, 3;0.5) (standard: ‘It’s my turn.’)

e. Very beautiful is that table now! (K, 3;4.4) (standard: ‘That table is very beautiful now.’)

Hence, utterances using lexemes from a single language, with non‐standard word order, can be found in both children’s speech. An example from M with non‐standard order of core arguments is Languages 2018, 3, 40 19 of 24 given in (32):

32. [Context: Dividing chocolates among four family members, but father is not present.] Can we choose one more? Let’s pretend that this one chose Daddy. (standard: ‘Let’s pretend that Daddy chose this one.’ (M, 7;8.24)

AllAll of of these these can can bebe analysedanalysed asas examplesexamples ofof structuralstructural transfer,transfer, as as the the translation translation equivalents equivalents are are grammaticalLanguagesgrammatical 2018, 3 in,in x Estonian.FOREstonian. PEER REVIEW ExamplesExamples ofof untargetlikeuntargetlike wordword orderorder inin “monolingual” “monolingual” utterancesutterances19 (with( withof 23 lexemeslexemes from from one one language) language) puts puts the the code-switched code‐switched utterances, utterances, as as in in (33), (33), in in a a new new light: light:

33. a. pääsuke like this is done. (M, 7;5.4) 4 Plural objectsswallow. in EstonianNOM.SG perfective clauses take nominative case; hence, the lack of object‐marking in this example ‘This does is not how disentangle you do the intendedswallow argument (=gymnastics structure pose).’ of this utterance.

b. I made with a harilik pliiats the joone-d, but then I colored outside the lines. regular pencil.NOM.SG line.NOM.PL ‘I drew the lines with a pencil, but then I colored outside the lines.’ (M, 7;0.5)

If thethe clausesclauses inin (33)(33) areare analysedanalysed withwith referencereference toto aa standardstandard viewview ofof monolingualmonolingual EnglishEnglish grammar, theythey areare counterexamples toto thethe Morpheme Order Principle. But compared to ( (28)28) and ( (32),32), the constituent constituent order order is is similar similar in in the the utterances utterances with with and and without without code code-switching.‐switching. If the If speaker the speaker uses usesnonstandard nonstandard order order in “monolingual” in “monolingual” utterances, utterances, then there then thereis no isreason no reason to expect to expect her to her dra tow draw on a onstandard a standard MLF MLFin code in code-switched‐switched utterances. utterances. This Thisdoes doesnot mean not mean that thatthe MOP the MOP is followed is followed here, here, but butrather rather that thatthe MOP the MOP is not is meaningful not meaningful in a context in a context in which in whichthe two the languages two languages so thoroughly so thoroughly interact interactas to make as it to difficult make it to difficult identify to a identifysingle languag a singlee as language the source as of the the source grammatical of the grammatical frame. This would frame. Thislogically would apply logically to the apply MLF itself to the as MLF well. itself as well. More generally,generally, the the MLF MLF model model assumes assumes a systema system of rulesof rules which which organise organise speakers’ speakers’ language language use, withuse, with one ofone the of languages the languages imposing imposing its rules its rules on any on given any given utterance. utteran Yetce. research Yet research has shown has shown great permeabilitygreat permeability between between the two the languages two languages in a bilingual’s in a bilingual’s mind, withmind, constant with constant coactivation coactivation and mutual and influence.mutual influence. If “every If “every bilingual bilingual is an is attriter” an attriter” (Schmid (Schmid and and Köpke Köpke 2017 2017),), then then children children withwith two (incompletely(incompletely acquired)acquired) firstfirst languageslanguages will inevitablyinevitably show effects ofof bilingualism,bilingualism, most likely in both languages.

5. Discussion and ConclusionsConclusions Child speech provides an important testing ground for theories of linguistic linguistic structure and languagelanguage processing, butbut itit alsoalso comescomes withwith complications forfor analysis.analysis. It is difficult difficult to judge whether nonstandard children’schildren’s utterances are innovations or speech errors, as reflectionsreflections of their level of language competence. competence. Bilingual Bilingual children’s children’s metalinguistic metalinguistic awareness awareness may involve knowledge ofof grammar and code-switching.code‐switching. The grammatical knowledge is dynamic in development,development, permeablepermeable between a bilingual’s bilingual’s languages,languages, and and difficult difficult to to capture. capture. SpeechSpeech production demonstrates the knowledge in operation, butbut alsoalso demonstratesdemonstrates itsits fluidity.fluidity. The childrenchildren analysed in this dataset produce a variety of code-switchingcode‐switching styles:styles: SomeSome examples show sensitivity sensitivity to to a MLF, a MLF, others others clearly clearly flout the flout System the System Morpheme Morpheme and Morpheme and Morpheme Order Principles. Order EvenPrinciples. where Even the MLFwhere model the MLF allows model for variability,allows for thevariability, extent of the variability extent of invariabi theselity data, in withinthese data, and acrosswithin individuals,and across individuals, and within and utterances, within utterances, is striking. Theis striking. children’s The languageschildren’s affectlanguages one anotheraffect one in moreanother fundamental in more fundamental ways than ways lexical than insertion, lexical insertion, with examples with examples of structural of structural transfer acrosstransfer various across domains.various domains. This indicates This indicates that the that ML structuresthe ML structures assumed assumed to underlie to underlie the utterances the utterances may not may always not bealways the relevant be the relevanones. Analystst ones. Analystsmust beespecially must be especiallycareful to avoid careful imputing to avoid grammatical imputing grammatical knowledge toknowledge (even balanced to (even bilingual) balanced children bilingual) who children do not yetwho have do not it, or yet assuming have it, asor targets assuming monolingual as targets structuresmonolingual which structures are not wellwhich founded. are not Thewell SMP founded. violations The SMP may beviolations developmental, may be anddevelopmen more prominenttal, and inmore early prominent code-switching, in early code as suggested‐switching, by as Paradis suggested et al. by(2000 Paradis). The et al. MOP (2000 is). repeatedly The MOP is violated repeatedly in thisviolated dataset, in this whereas dataset Paradis, whereas et Par al.adis report et al. low report levels low of levels MOP of violations MOP violations in their in French-English their French‐ data.English This data. may This be may due be to due greater to greater permissible permissible variability variability in constituent in constituent order order in Estonian in Estonian than than in in either French or English, leading to weaker structural adherence to word order in general, i.e., in the bilingual children’s English as well. There is a clear gap in existing research on children’s use of code‐switching. In order to untangle individual differences, developmental effects and the effects of language typology and sociolinguistic context, more detailed research is needed of the kind represented in Paradis et al. (2000). In order to more systematically investigate these variables, we need larger, controlled samples of spontaneous speech. Ideally, various language pairs with diverse, grammatically meaningful differences (of the kind discussed under stem changes and constituent order) need to be compared. Languages 2018, 3, 40 20 of 24 either French or English, leading to weaker structural adherence to word order in general, i.e., in the bilingual children’s English as well. There is a clear gap in existing research on children’s use of code-switching. In order to untangle individual differences, developmental effects and the effects of language typology and sociolinguistic context, more detailed research is needed of the kind represented in Paradis et al.(2000) . In order to more systematically investigate these variables, we need larger, controlled samples of spontaneous speech. Ideally, various language pairs with diverse, grammatically meaningful differences (of the kind discussed under stem changes and constituent order) need to be compared. The MLF framework is useful as a tool for analysis, but it has its limitations. The assumption that targeted structures derive from a monolingual, identifiable and independent ML is problematic, especially for children’s speech, but also for adults. Critics have pointed to a “misplaced faith in the role of the Matrix Language” and the unfounded assumption that bilingual speakers draw on clearly identifiable and distinct languages (Gardner-Chloros 2005, p. 91). As noted by Alvarez-Caccamo(1998), “research should first convincingly prove that (a) speakers who code-switch possess two (or more) identifiable linguistic systems or languages, each with its identifiable grammatical rules and lexicon; and (b) ‘code-switched’ speech results from the predictable interaction between lexical elements and grammatical rules from these languages” (Alvarez-Caccamo 1998, p. 36). Moreover, as noted by Gardner-Chloros(2005), “a prescriptive element can creep in: The outcome of specifying a ‘grammar’ of CS is that there appears to be a right and wrong way to code-switch, or at least a ‘possible’ and an ‘impossible’ way” (Gardner-Chloros 2005, p. 91). Differences between children’s and adults’ code-switching derive from many factors. The two children in this case study show differences in metalinguistic awareness and approaches to bilingual language usage, as well as change over development. Both, however, are sensitive to linguistic structure and typological differences between their languages. Individual differences may affect children’s code-switching more than adults’, due to their less developed knowledge of the morphosyntactic systems; see also Paradis(2011), who found that child-internal factors trumped external factors in language outcomes in a larger-scale study of second language acquisition. Children have not learned the complete adult grammars, and do not fully conform to the constraints posited by the MLF model. However, adults may never have as clear a set of rules guiding their language usage as the model assumes either. Research in bilingualism and language attrition has shown that languages are in constant interaction in bilinguals, and that parallel activation and crosslinguistic competition affect both the first and second language (Kroll and Bialystok 2013; Schmid and Köpke 2017). This casts doubt on the enterprise of comparing bilinguals’ language use to any static, monolingual model of grammar. We expect to find cross-linguistic transfer among bilingual children, whose linguistic knowledge is dynamic, developing and dependent on context. The examples of convergence and structural transfer in the present study show that the MOP may not be relevant, and hence may not be violated; yet this raises the question of when it is relevant to compare bilingual production to a monolingual model of clausal grammar. The assumptions of the MLF listed in Section 1.2 are all problematic: (1) A set of formal, grammatical rules cannot characterise spoken language, as a creative endeavour, performed online, even if those rules underlie abstract linguistic competence. (2) The data and discussion of convergence, along with a growing body of research, casts doubt on the notion that a bilingual’s two languages are mentally represented as independent grammars, and makes it clear that (3) a single ML is not always possible to identify. (4) While code-switching may adhere to abstract rules, surface-level structures also emerge in the course of production, and (5) code-switching behaviour can be influenced by various factors beyond morphosyntactic structure. These points apply equally to adult spoken language. When analysing child language, however, it is critical to bear in mind the dynamic nature of linguistic knowledge and production. This is not to say the children are not aware of speaking two languages Languages 2018, 3, 40 21 of 24 with differentiated lexicons and grammatical systems, but that the use of the two can be much more fluid than what the models capture. A more universal model may have to (a) replace constraints with tendencies in bilingual usage, (b) allow for more typologically sensitive nuance, (c) allow for construction-level analysis and effects of crosslinguistic influence and (d) assume that the languages interacting in bilingual usage are interdependent, dynamic, and negotiable outcomes of language use, rather than sets of rules imposed on usage. This would mean losing the principled structure of the MLF or other constraint-based models, but would mean gains in descriptive adequacy. The extent to which code-switching is subject to rules may itself be variable across contexts, considering the typological range of human languages, and the flexibility of language in use.

Funding: The funding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results. Acknowledgments: I gratefully acknowledge support from internal grants from the University of Tartu during the writing of this paper, and support from the Centre of Excellence in Estonian Studies (European Union, European Regional Development Fund) during revisions. My sincere thanks also to the editors of this special issue, and two anonymous referees, all of whose comments helped to improve the paper. All remaining weaknesses are my own. Conflicts of Interest: The author declares no conflict of interest. Although, as stated, the language analysed derives from the author’s own children, the subjectivity this necessarily entails is not deemed as influencing the analysis or conclusions. On the contrary, the type of data analysed in this article is enhanced by the knowledge of background and context available to the author as a “privileged” inside observer.

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