UCLA Working Papers in Linguistics, vol.0, June 2000 Papers in Lakhota—Munro (ed.) THE PRODUCTIVITY OF INFIXATION IN LAKHOTA* ADAM ALBRIGHT [email protected] A growing body of work on morphological irregularity has shown that the productivity of irregular morphological processes is sensitive to phonological context. However, these studies have focused almost exclusively on patterns of irregularity found in European languages. In this paper, I discuss a typologically different pattern of irregularity found in Lakhota: person marking appears as a prefix for some verbs, and as an infix for others. I combine computational modeling of the Lakhota lexicon and an experimental “wug” test, to show that infixed person marking is highly sensitive to context, just like other types of morphological irregularity. 1. INTRODUCTION It is not uncommon in the world’s languages for a particular morpheme to surface variably as an infix or as a prefix/suffix. One of the insights of McCarthy and Prince (1993), further developed in the OT literature, is that the decision to infix is often driven by prosodic considerations in the phonology. For example, possessive markers in Ulwa are placed after the first foot of the root, with the result that they are infixed in roots that are longer than one foot, and suffixed in words which contain just one foot. A second consideration which can drive infixation is syllable structure. An example of this is the morphemes -um- and -in- in Tagalog, which are prefixed to vowel-initial roots, but infixed in consonant-initial roots to create CV syllables and avoid VC syllables. One final consideration which has been argued to drive variable infixation is the local segmental environment. For example, Crowhurst (1998) points out that in at least some varieties of Toba Batak, the -um- morpheme which is cognate to Tagalog -um- is infixed only after certain consonants (/t k s d d g r l h/). In all of these cases, the analytical goal has been to make sense of a predictable distribution (infix vs. affix) in terms of its satisfaction of prosodic phonological constraints. In this paper, I will consider a case which has received less attention in the literature: morphemes which * I would like to thank our Lakhota teacher Mary Iron Teeth, who patiently provided difficult judgments about silly made-up words and about unusual uses of actual words — her good-natured willingness to play the “elderly aunt” game week after week has been truly remarkable. I would also like to thank Pam Munro, whose generous willingness to share her Lakhota Verb List made this analysis possible. Comments and suggestions are gratefully welcomed. 2 UCLA Working Papers In Linguistics, vol.0 may surface unpredictably as prefixes or infixes. The example I will focus on is person marking in Lakhota, as illustrated in (1): (1) Variable position of first singular subject marker -wa-: a. Prefixed: lówan ‘he sings’ ~ wa-lówan ‘I sing’ núwe ‘he swims’ ~ wa-núwe ‘I swim’ káge ‘he does/makes’ ~ wa-káge ‘I do/make’ b. Infixed: máni ‘he walks’ ~ ma-wá-ni ‘I walk’ aphé ‘he hits’ ~ a-wá-phe ‘I hit’ hoxpé ‘he coughs’ ~ ho-wá-xpe ‘I cough’ Such morphological irregularity poses not only an analytical problem for the linguist, but also a learning problem for the language learner. At the most basic level, for each word the learner must learn whether that word takes prefixation or infixation. However, this task might be simplified considerably if one could predict the behavior of words somehow, and if one pattern could be designated as a “default” to cover the majority of cases. In order to do this, we must be able to generalize over individual lexical items in some fashion. One scheme for how children might do this is the “Minimal Generality” hypothesis, outlined out by Albright and Hayes (1998) — namely, that children attempt to make sense of apparently arbitrary morphological patterns by paying careful attention to the phonological form of the roots involved. Under this view, the acquisition process is seen as a deliberate search for patterns which help predict class membership; as Zubin and Köpcke (1981, p.439) phrase it, “[w]e know that children are not passive consumers of morphological irregularity.” The end result is that languages have phonological regularities which line up with morphological irregularity, to produce a class system where membership is sort of — but not completely — arbitrary. The relationship between morphological irregularity and phonological form has been investigated for languages like English (Prasada and Pinker 1993) and for Italian verb classes (Albright 1998), but it has never been tested in a language with variably positioned morphemes. The goal of this paper, therefore, is to extend this line of investigation to Lakhota, in order to test the influence of phonology on morphology in a typologically different language. I will start with an overview of the place of affixation in existing Lakhota words, offering evidence that it is in fact a form of morphological irregularity, and reviewing some insights from Boas and Deloria (1941) on this matter. Next, I will outline an attempt to discover statistical tendencies computationally, using an automated pattern-discoverer developed by Albright and Hayes (1998). The goal of this section will be to uncover Albright—Productivity of Infixation 3 “islands of reliability” — that is, phonological neighborhoods in which words are especially likely to prefix or infix. I will then try to show that native speakers are in fact aware of these “islands,” and that phonological form does play a major role in shaping intuitions about how novel words should inflect. 2. THE POSITION OF SUBJECT MARKERS IN LAKHOTA 2.1. Overview of subject markers Subject agreement is marked in Lakhota by person and number affixes; the person affixes are either prefixed or infixed, while the plural marker -p is suffixed. The person markers can be divided into two series, which I will label as “I” and “II” (following Munro 1989).1 The subject markers for all persons are shown in Table 1. Table 1: The subject marking affixes of Lakhota “Series I” “Series II” (y-initial stems) wa un(k)*...p bl uny...p ma un(k)*...p ya ya...p l l...p ni ni...p ...p y y...p ...p *1pl -un- includes k before a vowel Boas and Deloria (1941) state that “[i]t is not possible to give absolutely consistent rules for the position of personal pronouns” (i.e., affixes) (p.78). As seen from example (1) above, the marker is prefixed for some verbs, and infixed for others. Therefore, the position of subject marking is to a certain extent unpredictable, and must be listed on a verb-by-verb basis. It is natural at this point to wonder how we can be so sure that the position of subject marking is not driven by phonotactic pressures in Lakhota. After all, the verbs in (1a) and (1b) are similar in structure, but they are not exactly minimal pairs. Is it possible that the alternation between prefixiation and infixation is in fact conditioned by a phonological environment, and we have simply failed to recognize the correct generalization? Without being able offer exact minimal pairs, I can not rule this possibility out completely; however, I can offer several types of evidence which make it seem unlikely. 1 The difference between Series I and Series II subject marking can generally be interpreted as an active/stative distinction; however, Munro has pointed out that some Series II verbs are not obviously stative, so the behavior of a verb is not completely predictable from its subcategorization properties. 4 UCLA Working Papers In Linguistics, vol.0 The first fact which makes a phonotactic explanation unlikely is that verbs with fully parallel structure (stress, manner of articulation, etc.) can take different patterns. Thus, the verbs lówan ‘sing’ and máni ‘walk’ in (1) are both composed of sonorants and have the same stress pattern, but one takes infixation and the other prefixation. In addition, Lakhota possesses other affixes which have similar phonological structure, but which can never infix. For example, the indefinitive object (valency-reducing) affix wa- is homophonous with the Series I first person marker, but it is prefixed for all verbs (including those which take infixed subject marking). Therefore, we can infer that it would be phonotactically legal to prefix the subject markers for all verbs. Finally, it appears that for a certain number of verbs, the subject markers may even be allowed in more than one position. In (2) we see that the verb washícu ‘be a white man’ allows either prefixation or infixation, while the verb wichásha ‘be a man’ allows only infixation. (2) Variable affix positions for some verbs a. washícu ‘be a white man’ wamáshicu ‘I am a white man’ mawáshicu ‘I am a white man’ b. wichásha ‘be a man’ wimáchasha ‘I am a man’ *mawíchasha ‘I am a man’ The two verbs in (2) are quite similar phonologically, but they have different morphological properties — therefore, it really does seem that the position of subject marking can not be reduced to a phonotactic effect. A second hypothesis which should be considered is a morphosyntactic one, in which infixing verbs are considered complex somehow. One approach along these lines would be to analyze infixing verbs as compounds, and then ensure that subject marking is prefixed to the second verb (the head of the compound) before the first verb is compounded to it. This approach would run into problems, however, with affixes that are always prefixed, such as the indefinite object wa-. We would have to say that these affixes are added after the compound is formed, but these suffixes typically affect subcategorization requirements (usually by changing valency), and subcategorization requirements are a property of the head of the compound — so why should they be added to the complement? In addition, inflectional elements like person marking are typically the last elements to be added in a verbal complex, so it would be quite surprising to find a language where person marking precedes valency-changing derivational morphology.