Chapter 5: Syntax

 

Chapter 5: Syntax

Syntax is the branch of linguistics concerned with the rules and principles that govern the structure of sentences in a language. It studies how words combine to form phrases and sentences.

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5.1 Sentence Structure

What is a Sentence?

• A sentence is a grammatical unit consisting of one or more words that express a complete thought.
• Sentences typically contain a subject and a predicate.

Basic Sentence Types

• Simple Sentence: Contains one independent clause (e.g., The dog barked.)
• Compound Sentence: Contains two or more independent clauses joined by conjunctions (e.g., The dog barked, and the cat ran.)
• Complex Sentence: Contains one independent clause and at least one dependent clause (e.g., The dog barked when the mailman arrived.)

Sentence Constituents

• Sentences are composed of constituents, which are groups of words functioning as a single unit.
• Main constituents: Subject, Predicate, Object, Complement, and Adverbials.

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5.2 Phrase Structure Rules

Phrase structure rules (also called rewrite rules) describe how sentences are built from phrases and how phrases are constructed from words.

Common Phrase Types

• Noun Phrase (NP): A phrase headed by a noun (e.g., the big dog)
• Verb Phrase (VP): A phrase headed by a verb (e.g., barked loudly)
• Adjective Phrase (AdjP): A phrase headed by an adjective (e.g., very happy)
• Adverb Phrase (AdvP): A phrase headed by an adverb (e.g., quite quickly)
• Prepositional Phrase (PP): A phrase headed by a preposition (e.g., on the table)

Basic Phrase Structure Rules

• S → NP + VP
  A sentence consists of a noun phrase followed by a verb phrase.
• NP → (Det) + (AdjP) + N + (PP)
  A noun phrase may have a determiner, adjectives, a noun, and an optional prepositional phrase.
• VP → V + (NP) + (PP) + (AdvP)
  A verb phrase consists of a verb possibly followed by a noun phrase, prepositional phrase, or adverb phrase.
• PP → P + NP
  A prepositional phrase consists of a preposition followed by a noun phrase.

Note: Parentheses indicate optional constituents.

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5.3 Constituents and Tree Diagrams

Constituents

• Constituents are word groups that function as units within larger structures.
• Tests for constituency include substitution, movement, and coordination tests.

Tree Diagrams

• Tree diagrams visually represent the hierarchical structure of sentences according to phrase structure rules.
• Each node represents a constituent, and branches show how constituents are composed of smaller parts.

Example Tree Diagram for:

The cat sat on the mat.

mathematica

Copy

        S

      /   \

     NP    VP

    /     /  \

  Det    V    PP

  |      |    /  \

 The    sat  P    NP

               |    / \

              on  Det  N

                    |    |

                   the  mat

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5.4 Transformations

Transformations are syntactic operations that change sentence structure without changing meaning fundamentally.

1. Passive Transformation

• Changes an active sentence to passive voice.
• The object of the active sentence becomes the subject of the passive sentence.
• Example:
• Active: The chef cooked the meal.
• Passive: The meal was cooked by the chef.

Structure change:

• Active: S → NP(subject) + VP (V + NP(object))
• Passive: S → NP(object) + auxiliary verb (be) + past participle + (by + agent)

2. Question Formation

• Forming questions often involves moving an auxiliary verb to the front of the sentence.
• Example:
• Statement: She is reading a book.
• Question: Is she reading a book?

Yes/No questions:

• Move the auxiliary verb before the subject.

Wh- questions:

• Use a wh-word (what, where, why, who, etc.) and move it to the front.
• Example: What is she reading?

3. Other Transformations

• Negation: Adding negative elements like not to the sentence.
• She is happy. → She is not happy.
• Topicalization: Moving a constituent to the front for emphasis.
• I read that book. → That book, I read.

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Summary

Topic	Description	Example
Sentence structure	Sentences composed of subject + predicate + objects, etc.	The dog barks.
Phrase structure rules	Rules showing how phrases/sentences are built	S → NP + VP
Constituents	Word groups functioning as units	NP, VP, PP
Tree diagrams	Visual representation of sentence structure	Tree diagram of The cat sat on the mat.
Transformations	Syntax operations like passive voice, questions	Active → Passive; Is she coming?