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Phrase Structure Grammar Announcements INTD0112 ¾ I activated the link to the LAP guideline questions online. This will help you as Introduction to write your LAP report. ¾ The other day there was this story on the Linguistics main page of Yahoo!: ¾ http://answers.yahoo.com/question/index? Lecture #14 qid=20090929153251AAYjuZV Oct 26th, 2009 Today’s puzzle Summary of last class ¾ Syntax is the study of sentence structure. ¾ Bob hit the elf on the table with the hat. ¾ They key notion to understanding sentence structure in human language is “constituency.” ¾ How many meanings can you get out of this sentence? ¾ Constituency of a string of words can be determined by objective diagnostics: substitution test, movement test, and clefting. Phrase structure: Phrase structure: Heads and complements Heads and complements ¾ Once we determine that a string of words is a ¾ Remember from our discussion of morphology constituent, the next step is to determine its that there are four major lexical categories in syntactic type, or category. human language (well, prepositions are iffy, but ¾ For this we make a distinction between a head let’s assume they are lexical for now): and a complement. Noun (N), ¾ The head is the central word in a string, the one that requires other elements to be there. Verb (V), ¾ The complement is the part of the string that is Adjective (A), and there because of the head (if needed). Preposition (P). ¾ The head and the complement together form ¾ As we should expect, each one of these what we call a phrase, and the syntactic category of the phrase is that of the head. categories can be the head of a phrase. 1 Phrase structure: Phrase structure rules Heads and complements ¾ So, ¾ We express this head-complement - “picture of the boys” is a noun phrase (NP), since the head of the string is the N relationship by means of rewriting rules, “picture”. which we call phrase structure rules, as - “ate the sandwich”, by contrast, is a verb phrase (VP), since the head of the string is the V in the following examples: “ate”. NP Æ N PP - “in the office” is a prepositional phrase (PP), since the head of the string VP Æ V NP is the P “in”. - “fond of chocolate” is PP Æ P NP an adjectival phrase (AP), since the head of the string is the A “fond”. AP Æ A PP Subcategorization Subcategorization ¾ Notice that heads differ as to whether they need ¾ Furthermore, transitive verbs differ in complements and how many they take. Technically, we say they have different whether they subcategorize for an NP subcategorization properties. complement like “buy” above, or a PP ¾ For example, transitive verbs require complement as “talk”: complements, but intransitive verbs do not: I talked [ to his boss]. John slept. PP *John slept the dog. ¾ Some transitive verbs even require two John bought a new car. complements, such as “give” and “put”: *John bought. She gave [NP me] [NP money]. ¾ Remember the eat-devour puzzle? Alice put [NP the car] [PP in the garage]. Phrase structure: Specifiers X'-schema for phrase structure ¾ Notice finally that while complements may be ¾ To generalize, using X as a variable ranging obligatory (depending on the subcategorization over all heads, every phrase has the internal properties of the head), a head may also have structure below: nonobligatory “satellite” elements, called (5) XP specifiers, e.g., ru - an adverb (Adv) of a V: sometimes rented a Specifier X' car. ru -a determiner (Det) of an N: the linguist X complement -a degree (Deg) word of an A or a P: very nice/ ¾ (Note: The intermediate level between X and XP is straight into the room pronounced X-bar.) ¾ We can then apply this X'-schema to all heads. 2 NP VP (6) NP (7) VP ru ru Det N' Adv V' | ru aN PP | ru | ru quickly V NP picture P NP | ru | ru ate Det N of Det N || || the boys the sandwich PP AP (8) PP (9) AP ru ru Deg A' Adv P' | ru | ru very A PP right P NP | ru | ru fond P NP into Det N || || of N | the office chocolate So, what’s the head of a sentence? AuxP ¾ Consider now sentences such as John will eat the pizza. (10) AuxP ¾ Since we know that “John” is a constituent, it ru must be that “will eat the pizza” is also a NP Aux’ constituent. But what kind of constituent is it? John ru ¾ Let’s assume that the head here is the modal Aux VP verb “will,” whose complement is the VP “eat the will pizza”, and whose specifier is the subject “John”, ru and that the whole string is an Auxiliary Phrase VNP (AuxP), as shown in the following tree diagram: eat the pizza 3 AuxP AuxP ¾ But now consider this sentence: ¾ The structure of “John ate the pizza” will look like that, then: (11) John ate the pizza. (12) AuxP ¾ Since the subject “John” is still present, we have ru to assume that there is some “Aux” element in NP Aux' the sentence, since subjects are specifiers of John ru Aux. But it does not look like there is a modal Aux VP +past verb there. ru VNP ¾ Linguists assume that the tense morpheme is eat the pizza actually a form of Aux (or that Aux is a form of tense, but this is a labeling issue). ¾ Question: How does “eat” and “past” become the word “ate”? One more category CP ¾ Consider the complement (also called ¾ Using the same X'-schema, this must be a embedded clause) of the verb “says” in head-complement relation (though no (13) John says [that he will eat the pizza]. specifier is available here, but remember that specifiers are optional). ¾ Now, the embedded clause looks identical to the AuxP in tree #10, except that it has an extra ¾ Let’s assume then that a complementizer element: the so-called complementizer that, (abbreviated C) also heads a phrase, and which is said to carry the illocutionary force of that its complement is AuxP, as shown on the clause, i.e., it marks the clause as either declarative, interrogative, etc. the next slide: CP (embedded) CP (14) CP ¾ But if C determines the illocutionary force of a ru clause, then it must also be present in matrix CAuxP (i.e., non-embedded) clauses, though not that ru pronounced. NP Aux’ he ru Aux VP ¾ In other words, the structure of “John will eat will ru the pizza” is actually as on the next slide, with V NP a null C heading the sentence and indicating eat the pizza that this is a declarative sentence: 4 A mini-grammar for English: CP (main) Phrase structure rules (15) CP ¾ So putting all of this together, here’s a mini-grammar for English phrase structure, where brackets (or parentheses, ru depending on your dialect) indicate optionality: (Note: This is C AuxP by no means an exhaustive list.) declarative (16) Ø ru CP Æ C AuxP NP Aux’ AuxP Æ NP Aux' John ru Aux' Æ Aux VP VP Æ V (NP) (PP) Aux VP VP Æ V (CP) will ru VP Æ V AP V NP NP Æ (Det) N (PP) PP Æ (Deg) P NP eat the pizza AP Æ (Deg) A (PP) A mini-grammar for English: Structural tree of an English sentence Lexical rules ¾ A grammar must also include a set of rules that CP insert words from the lexicon under “terminal” ru CAuxP nodes in the tree, e.g., ru N Æ {man, dog, justice, …} NP Aux' V Æ {love, hit, leave, …} ty ru Det N Aux VP Aux Æ {will, must, Past, …} ru Det Æ {the, a, an, his, some, …) VPP ru etc. P NP ¾ As you should expect, these are called lexical ru insertion rules. Det N Our children like this music. CP ei Cdeclarative AuxP Ø eo Time for some tree-drawing fun. NP Aux' ru ei Let’s draw trees for some sentences. Det N Aux VP our children -past ru V NP like ru Det N this music 5 John is proud of his medals. CP ei Cdeclarative AuxP Ø ei The linguist knows that this language has NP Aux' | ei become extinct. N Aux VP | -past ru John V AP is ru Adj PP proud ru PNP of ru Det N his medals CP wo What do trees tell us? Cdeclarative AuxP Ø wo NP Aux' ¾ Tree diagrams show three aspects of ru ru speakers’ syntactic knowledge: Det N Aux VP a. the linear order of the words in the sentence, the linguist -past ri V CP b. the groupings of words into particular know ei syntactic constituents (e.g. NP, VP, etc.), and Cdeclarative AuxP that ei c. the hierarchical structure of these NP Aux' constituents (that is, the fact that constituents eu ru contain constituents inside them, which in turn Det N Aux VP this language has ri contain other constituents, and so on and so V AP forth). become extinct Aspects of syntactic knowledge revisited Grammaticality revisited ¾ Remember that our mental grammar provides us ¾ We have already seen that our grammar with certain aspects of syntactic knowledge: can generate grammatical sentences. a. the ability to formulate grammaticality Now we also need to make sure that it judgments, b. the ability to produce and understand an infinite does NOT generate ungrammatical number of sentences, sentences, such as the one below: c. the ability to recognize cases of ambiguity, and *Boy the ball kicked the. d. the ability to relate sentences to each other. ¾ How does a phrase structure grammar ¾ For our theory of grammar to be adequate, it has rule out such bad sentences? to account for all these aspects of grammatical knowledge.
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