Chapter Eight Syntax.

Slides:



Advertisements
Similar presentations
Natural Language Processing Syntax. Syntactic structure John likes Mary PN VtVt NP VP S DetPNVtVt NP VP S Every man likes Mary Noun.
Advertisements

Chapter 4 Syntax.
Language and Cognition Colombo, June 2011 Day 2 Introduction to Linguistic Theory, Part 4.
SYNTAX Introduction to Linguistics. BASIC IDEAS What is a sentence? A string of random words? If it is a sentence, does it have to be meaningful?
PSY 369: Psycholinguistics Some basic linguistic theory part2.
What is Syntax?  The rules that govern the structure of utterances; also called grammar  The basic organization of sentences is around syntax  build.
Matakuliah: G0922/Introduction to Linguistics Tahun: 2008 Session 11 Syntax 2.
Chapter 3 Describing Syntax and Semantics Sections 1-3.
Lect. 11Phrase structure rules Learning objectives: To define phrase structure rules To learn the forms of phrase structure rules To compose new sentences.
Dr. Ansa Hameed Syntax (4).
Syntax: The analysis of sentence structure
Syntax.
Grammar Nuha Alwadaani.
Syntax Nuha AlWadaani.
Phonetics, Phonology, Morphology and Syntax
Linguistic Theory Lecture 3 Movement. A brief history of movement Movements as ‘special rules’ proposed to capture facts that phrase structure rules cannot.
Phrases and Sentences: Grammar
11 CS 388: Natural Language Processing: Syntactic Parsing Raymond J. Mooney University of Texas at Austin.
Three Generative grammars
Syntax: The Sentence Patterns of Language
1 LIN 1310B Introduction to Linguistics Prof: Nikolay Slavkov TA: Qinghua Tang CLASS 14, Feb 27, 2007.
Chapter 4 Syntax Part II.
Introduction to Linguistics
1.Syntax: the rules of sentence formation; the component of the mental grammar that represent speakers’ knowledge of the structure of phrase and sentence.
IV. SYNTAX. 1.1 What is syntax? Syntax is the study of how sentences are structured, or in other words, it tries to state what words can be combined with.
Natural Language Processing Lecture 6 : Revision.
NLP. Introduction to NLP Is language more than just a “bag of words”? Grammatical rules apply to categories and groups of words, not individual words.
1 Prof.Roseline WEEK-4 LECTURE -4 SYNTAX. 2 Prof.Roseline Syntax Concentrate on the structure and ordering of components within a sentence Greater focus.
Introduction to Linguistics Ms. Suha Jawabreh Lecture 19.
Syntax Sentence Structures. Generative Grammar This is the idea that grammar has a finite number of rules, BUT is capable of producing an infinite number.
Culture , Language and Communication
Rules, Movement, Ambiguity
1 Context Free Grammars October Syntactic Grammaticality Doesn’t depend on Having heard the sentence before The sentence being true –I saw a unicorn.
Natural Language Processing
Making it stick together…
ISBN Chapter 3 Describing Syntax and Semantics.
SYNTAX.
◦ Process of describing the structure of phrases and sentences Chapter 8 - Phrases and sentences: grammar1.
1 Chapter 4 Syntax Part III. 2 The infinity of language pp The number of sentences in a language is infinite. 2. The length of sentences is.
Syntax.
3.3 A More Detailed Look At Transformations Inversion (revised): Move Infl to C. Do Insertion: Insert interrogative do into an empty.
Welcome to the flashcards tool for ‘The Study of Language, 5 th edition’, Chapter 8 This is designed as a simple supplementary resource for this textbook,
College of Science and Humanity Studies, Al-Kharj.
Lecturer : Ms. Abrar Mujaddidi S YNTAX. I NTRODUCTION  In the previous chapter, we moved from the general categories and concepts of traditional grammar,
SYNTAX.
Chapter 4 Syntax a branch of linguistics that studies how words are combined to form sentences and the rules that govern the formation of sentences.
King Faisal University جامعة الملك فيصل Deanship of E-Learning and Distance Education عمادة التعلم الإلكتروني والتعليم عن بعد [ ] 1 King Faisal University.
King Faisal University جامعة الملك فيصل Deanship of E-Learning and Distance Education عمادة التعلم الإلكتروني والتعليم عن بعد [ ] 1 King Faisal University.
Natural Language Processing Vasile Rus
ENGLISH DEPARTMENT FACULTY OF LETTERS
Introduction to Linguistics
Syntax 2.
Grammar and Syntax.
Beginning Syntax Linda Thomas
An Introduction to the Government and Binding Theory
BBI 3212 ENGLISH SYNTAX AND MORPHOLOGY
SYNTAX.
4.3 The Generative Approach
Chapter Seven Grammar.
Part I: Basics and Constituency
What is Syntax?  The rules that govern the structure of utterances; also called grammar  The basic organization of sentences is around syntax  build.
Syntax.
CS 388: Natural Language Processing: Syntactic Parsing
BBI 3212 ENGLISH SYNTAX AND MORPHOLOGY
Chapter Eight Syntax.
Natural Language - General
Introduction to Linguistics
Natural Language Processing
Grammar and Syntax.
Parts of sentence & word order in English
Presentation transcript:

Chapter Eight Syntax

Syntax When we concentrate on the structure and order of components within a sentence we are studying the syntax of a language. Syntax (from Greek) = ‘putting together’ In early approaches to syntax, there was a focus on the description of the ordering of elements in the linear structure of the sentence. Recently, the focus shifted to the underlying rule system that we use to produce or ‘generate’ sentences.

In syntax, we focus on the “all and only” criterion. / i. e In syntax, we focus on the “all and only” criterion./ i.e. when analyzing any language, we account for all grammatically correct structures and only those structures. We have to check that any proposed grammatical rule has to produce only correct structures. E.g. to form a prepositional phrase we put a preposition before a noun ‘near London’, however, if we apply this rule to all prepositions and nouns we will produce incorrect phrases like ‘near tree’ or ‘with dog’ What’s a noun phrase? The revised definition (an article plus a noun/ a proper noun/ or a pronoun) Therefore, the rule can be fixed to say ‘a prepositional phrase in English consists of a preposition followed by a noun phrase’/ so the revised rule can produce well-formed structures ‘near the tree’ and ‘with the dog’ or ‘with you’

It is one of the goals of syntactic analysis. Generative grammar: the small and finite set of rules that are capable of producing a large and infinite number of well-formed structures. It is one of the goals of syntactic analysis. its called ‘generative’ because it can be used to generate or produce sentence structures and not just describe them. This type of grammar reveals two phenomena: 1/ how some sentences can appear different on the surface but they are actually closely related. 2/ how some sentences can appear similar on the surface but they are in fact different.

Deep and Surface Structure Two different sentences Charlie broke the window. (active) The window was broken by Charlie. (passive) The difference is in their surface structure However, both share the underlying structure (NP V NP)/ they are almost identical in their deep structure which is an abstract (unseen) level of structural organization. Thus, grammar must be capable of showing how a single underlying structure can become different surface structures.

Structural Ambiguity E.g. ‘Annie bumped into a man with an umbrella.’ ‘I once shot an elephant in my pajamas. ‘Small boys and girls.’ They have two underlying interpretations with the same surface structure. Syntactic analysis has to be capable of showing the structural distinction between these underlying representations.

Recursion Recursion: Repeatable any number of times. Grammar rules have to have the capacity to be applied more than once in generating a structure. E.g. ‘The gun was on the table near the window in the bedroom’ (we are repeating the rule of forming prepositional phrases) Also grammar has to have the ability to put sentences inside other sentences. E.g., ‘John believed that Cathy knew that Mary helped George.’

Tree diagrams One of the most common ways to create a visual representation of syntactic structure Uses symbols (e.g., N= noun, NP= noun phrase) It captures the hierarchal organization of the underlying structures of phrases and sentences/ shows clearly that there are different levels in the analysis E.g. ‘The girl saw a dog’ (see pgs. 99- 100)

Symbols used in Syntactic Analysis Most common symbols used in syntactic categories: S / N/ V/ Art/ NP/ VP/ Adj/ Pro/ PN/ Adv/ Prep/ PP (see p. 101) Three new symbols: 1- (→) means ‘consists of’ or ‘rewrites as’ e.g., NP → Art N The dog 2- round brackets ( ) means an optional constituent - e.g. NP → Art (Adj) N - The (small) dog. 3- curly brackets { } means only one of the elements can be selected/ instead of writing three separate rules I can join them in one rule: - e.g. NP → { Art N, Pro, PN} - the dog, it, Cathy ● (See p. 101 for the full list)

Phrase Structure Rules When we use a tree diagram we can think of it in two different ways: Static, a fixed representation of the structure of the sentence that is written in the bottom of the diagram Dynamic , it represents a way of generating not only that one sentence, but a large number of sentences with similar structures This is more appealing because it enables us to generate a very large number of sentences with a small number of rules. These rules are called:

Phrase structure rules: rules that state that the structure of a phrase of a specific type will consist of one or more constituents in a particular order. i.e., these rules represent the underlying or ‘deep structure’ of sentences in English. We can use these rules to present the information of a tree diagram in another format, e.g., NP → Art N S → NP VP It means ‘a sentence rewrites as (consists of) a noun phrase and a verb phrase’ NP → {Art (Adj) N, Pro, PN} VP → V NP (PP) (Adv) Adam broke the window near the shop aggressively. PP → Prep NP Near London

Lexical rules Lexical rules: they specify which words can be used when we rewrite constituents, e.g., PN → {Mary, George} It means ‘ a proper noun rewrites as (consist of) Mary or George’ N → {girl, dog, boy} Art → {a, the} Pro → {it, you} V → {followed, helped, saw} we can rely on these rules to generate grammatically correct sentences, e.g., A dog followed the boy. Mary helped George. (See p.103) notice sentences (1-6) all follow the structure (NP V NP) while (7-12) have different incorrect structures

As a way of visualizing how the phrase structure rules form the basis of these sentences we can draw them into tree diagrams and add to them the sentences (on the bottom of the diagram) (see p. 103)

Movement Rules The simple ‘phrase structure rules’ taken so far help in generating sentences in a fixed order (declarative forms/ statements) however, they cannot be used to make questions (interrogative forms) In order to make a question we have to move one part of the structure to a different position. This process is called a movement rule. E.g., You will help Mary. Will you help Mary?

Therefore, we have to expand the phrase structure rule to include an auxiliary verb (Aux) as part of the sentence. S → NP Aux VP (a phrase structure rule) Aux → {can, could, should, will, would} (a lexical rule) V → {follow, help, see} (a lexical rule) Now we can use these components to specify a movement rule that we can use to describe the structure of one type of questions (notice the use of a special arrow symbol) NP Aux VP Aux NP VP (a movement rule) This type of rule can be also illustrated by a two tree diagrams (see p.104) Using the same rules we can also generate other questions (see p. 105) they all have different surface structures with the same underlying ‘deep’ structure.

Back to recursion The phrase structure rules taken so far do not have ‘recursive’ elements. As mentioned earlier, in correct grammar, we have to be able to include sentences within sentences E.g., John believed that [Cathy knew that [Mary helped George]]. we notice that after the verbs believe and know, the word that is used to connect it to the following sentence

Complement phrases: The word that is called a complementizer (C). The role of it is to introduce a complement phrases (CP) E.g., [that Mary helped George] (CP) Mary helped George. (S) So we can identify CP as follows: a complent phrase rewrites as a complementizer and a sentence, CP → C S

We can also notice from the example that the CP [ that Mary helped George] came after the verb knew. This means we are using the (CP) as part of the verb phrase (VP) Thus we can write another rule that says that ‘a verb phrase rewrites as a verb and a complement phrase’ VP → V CP

Now, if we add these two new rules to two earlier rules we have taken before, we can see how recursion is applied in grammar: S → NP VP VP → V CP CP → C S This means we can use these rules to create an endless sentence containing other sentences. Its shown best through tree diagrams (See p. 106)