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Constituent Structure. Syntactic Categories. Parts of speech: Noun, Verb, Adjective, Adverb, etc. Evidence for syntactic categories: child language. The Wug Test (Jean Berko Gleason, 1958) was designed to understand children’s understanding of inflection. .
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Syntactic Categories • Parts of speech: Noun, Verb, Adjective, Adverb, etc. • Evidence for syntactic categories: child language. • The Wug Test (Jean Berko Gleason, 1958) was designed to understand children’s understanding of inflection.
Tongue slips of adult native speakers (Spoonerisms) “Sir, you’ve hissed my mystery class”. Intended: “Sir you’ve missed my history class.”
Ambiguity (Ambiguous sentences) Lexical ambiguity • John drove his car to the bank. • The hunter went home with five bucks in his pocket.
Structural ambiguity This type of ambiguity is caused by grouping words together in different ways. • The [tall bishop]’s hat • (The bishop is tall) • The tall [bishop’s hat] • (The hat is tall)
We can assign different grammatical structures to the same string of words. This is evidence showing that words form sub-groups (or CONSTITUENTS) within a phrase or sentence. These groupings are often crucial in determining the meaning of a sentence.
Words belonging to different syntactic categories Mistrust wounds. • “Suspicion hurts people.” • “We should mistrust injuries.” Can you interpret the following sentence? Time flies.
Amusing newpaper headlines Which word causes the ambiguity? • Reagan Wins On Budget, But More Lies Ahead • Squad Helps Dog Bite Victim
How do we identify a constituent? • She is crying. • The little girl wearing a red hat with a blue ribbon is crying. (1) Strings of words replacing a single word must be units (constituents.)
Malay • (i) Saya makan ikan besar itu I eat fish big that ‘I ate/am eating that big fish.’ • (ii) İkan besar itu saya makan fish big that I eat ‘That big fish I ate/am eating.’ (2)When a group of words can be moved as a unit, we can assume that the group froms a syntactic unit.
Malay • Orang tua itu makan ikan besar itu person old that eat fish big that ‘That old person ate the big fish.’ • ikan besar itu di-makan oleh anjing saya fish big that PASS-eat by dog my ‘That big fish was eaten by my dog.’ (3) The same string of words can occur in a variety of positions within the sentence, e.g. as subject and object.
Malay • Orang tua itu makan ikan besar itu person old that eat fish big that ‘That old person ate the big fish.’ • Siapa makan ikan besar itu • Who ate fish big that ‘Who ate that big fish?’ (4) When a group of words are replaced by a question word to form a content question, we can assume the group of words forms a unit.
Siapa makan ikan besar itu Who ate fish big that ‘Who ate that big fish?’ Answer1: Orang tua itu person old that ‘that old person Answer2: *tua itu ‘old that’ old that (5) Constituents can form the answer to a content question, whereas a string of words which is not a syntactic unit is not a possible answer.
Hierarchy Each constituent of a larger unit may itself be composed of smaller constituents. The CLAUSE is the smallest grammatical unit which can express a complete proposition.
A sentence may consist of several clauses. Can you identify the clauses in the following lines? Foxes have holes and birds of the air have nests, But the Son of Man has no place to lay his head.
PHRASE A single clause may contain several phrases. The coach’s wife introduced her little sister to the captain of the football team. [to [the captain [of [the [football team]]]]].
Football team Of the football team The captain of the football team To the captain of the football team
A single word may contain several morphemes. Dis-taste-ful Read-abil-ity Dis-en-tangle
This kind of structural organization is called a PART-WHOLE HIERARCHY: Each unit is entirely composed of smaller units belonging to a limited set of types. This is important in morphology, syntax, and phonology.
Identifying syntactic categories Traditional definitions of parts of speech are based on semantic properties. A NOUN is a word than names a person, place, or thing. A VERB is a word that names an action or event. An ADJECTIVE is a word that describes a state.
Traditional definitions fail to identify nouns like happiness, love, destruction, etc. • They cannot distinguish between the noun love and the adjective fond of. • They cannot distinguish the noun fool from the adjective foolish.
In Jabberwocky, we were able to distinguish most parts of speech even though they were mostly nonsense words. Also, children are able to form the plurals of nonsense words or words they’ve never heard before.
The identification of syntactic categories cannot be based on semantic factors. We need to address the following problems separately: • Which words belong together in the same class? • What name (or label) should we assign to a given class?
Answering Question 1 Words that share a number of grammatical characteristics are assumed to belong to the same class. Words that have distinct grammatical characteristics are assumed to belont to differen classes.
Fool vs foolish Modification by degree adverb vs adjective They are utter fools. *They are utter foolish. They are fools. They are very foolish. Inflection for number Fool, fools Foolish, *foolishes Comparative forms Fool-*fooler/*more fool Foolish-more foolish As subject of a clause Fools rush in where angels fear to tread. *Fools rush in where angels fear to tread. Identifying grammatical characteristics
Answering Question 2 Once the word classes in a particular language have been identified in this way, they can be assigned a label (Noun, Verb, etc) based on universal notional patterns. If there is a class whose prototypical members include most of the basic terms for concrete objects (dog, book,house), we would label that class NOUN.
If there is a class whose prototypical members include most of the basic terms for volitional actions (run, dance, eat), we would label that class VERB. The grammatical criteria used to determine word classes are diagnostic features rather than definitions. E.g. In English, not all adjectives can take the comparative and superlative suffixes.
Almost all languages have the lexical categories Noun and Verb, but there is a significant range of difference among languages.
PHRASES and PHRASAL CATEGORIES • A phrase must be a group of words which form a constituent. • A phrase is lower in the hierarchy than clauses. 1. Which phrases belong together in the same class? 2. What name (or label) should we assign to a given class?
Answering Question 1 • Internal structure of phrases e.g. An English noun phrase often begins with a DETERMINER (a, the, that, this) • Mutual substitutability: two phrases of the same category could potentially occur in the same positions. e.g. Phrases occuring in Object and Subject positions are NOUN PHRASES.
Answering Question 2 • In most phrases, there is a core word, called the HEAD of the phrase. • We name a phrase by the category of the head. e.g. That big fish is a NOUN PHRASE because its head is a noun (fish). e.g. very beautiful is an ADJECTIVE PHRASE because its head is an adjective (beautiful).
How do we know which word in the phrase is the head? How do we distnguish the head from the DEPENDENTS (i.e all the other elements in the phrase)?
The head is important because • it determines the grammatical features of the phrase as a whole. • it may determine the number and type of other elements in the phrase. • it is more likely to be obligatory than the modifiers or other non-head elements in the phrase.
The head determines the grammatical features of the phrase as a whole The new rice is in the barn. The new kittens are in the barn.
The head may determine the number and type of other elements in the phrase. • Prepositional phrases are complements of the adjective phrase I am [very grateful to you] John felt [sorry for his actions.] angry at someone, proud of someone, worried about something • Objects are complements of the verb phrase Mary is [reading a book]. James [showed his photo album to us]. Mary [runs] every morning.
The head is often obligatory in a phrase. • [The little girl wearing a red hat with a blue ribbon] was crying her eyes out. • [The little girl] was crying her eyes out. • [The girl] was crying her eyes out.
The head may be omitted in certain contexts • The third little girl was smarter than the second ___. • The good, the bad, and the ugly • The rich get richer and the poor get childen.
Major categories (can function as heads of phrases) Noun, verb, adjective, adverb, preposition Minor categories Conjunctions, interjections, determiners (includes articles, demonostratives, and quantifiers)
Tree diagrams representing the constituents of a clause In analyzing grammatical structure, we need to identify • The constituent parts which the sentence is formed. • The order in which these constitutents occur. The vertical lines inserted between the constitutents are helpful to describe grammatical structure.
Tree diagrams A Mother node C Daughter nodes B
A DOMINATES all of its daughter nodes; i.e. The daughters of daughters, daughters of its grand-daughters, etc. A mother IMMEDIATELY DOMINATES its own daughters. A CONSTITUENT is a string of words which is exhaustively dominated by some node.
PP P NP Det N on the beach
N Noun A Adjective V Verb P Preposition Adv Adverb Det Determiner Conj Conjunction NP Noun Phras AP ADjective Phrase VP Verb Phrase PP Prepositional Phrase S Sentence or Clause
The top-most node in any tree diagram is called the ROOT NODE. The terminal nodes at the bottom are sometimes called LEAVES. The No Crossing Constraint: lines from mother to daughter must not cross. The Single Mother Constraint: each node after the root node must be the daughter of exactly one other node.
The motivation for imposing these constraints is that by allowing crossing lines or multiple parenthood, we would end up with potentially complex structures which are never found in real human languages.
Phrase Structure Rules The task of the linguist is to find out the rules which allow the speakers of a language to construct and comprehend novel sentences. The rules needed to produce Phrase Structure Trees are known as Phrase Structure Rules and have the following form: A B C
A B C • This rule says that a node labelled A may immediately dominate two daughters labelled B and C in that order. • This is a CONTEXT FREE rule, i.e. there is no conditioning environment stated in this rule.
Each node of a Phrase Structure tree must be permitted (or LICENSED) by a phrase structure rule in order to be legal. To license (or, to generate) the prepositional phrase “on the beach” (slide 44), we would need these rules: