05 Syntax

How syntax organizes words

Syntax studies how words combine into phrases and sentences, and how their arrangement contributes to interpretation. Sentences have hierarchical structure: words form groups, and those groups can function as units within larger groups. A sentence is therefore not simply a row of words.

Finding constituents

A constituent is a word or group of words that functions as a unit in a sentence. In The curious child opened the box, the curious child forms a unit that can function as the subject, while the box forms a unit that can function as the object.

Linguists use several diagnostics to investigate whether words form a constituent:

• Substitution: Replace a word group with a form that can occupy the same position. The curious child can be replaced by she: She opened the box.

• Movement: Move a group to another position. The box can be fronted for emphasis: The box, the child opened.

• Question and answer: A group that can serve as a natural answer is evidence of a constituent. “What did the child open?” — The box.

• Coordination: Groups of similar type can often be joined with and or or, as in the curious child and the tired adult.

These tests provide evidence, not infallible rules. A test may fail because of the particular sentence or construction, and a string that passes one test may need further investigation. Analysts compare multiple diagnostics and consider how the language works as a whole.

Phrases and their structure

A phrase is a constituent organized around a central word called its head. The head determines the phrase’s category and contributes key properties to it. A noun heads a noun phrase (NP), a verb a verb phrase (VP), an adjective an adjective phrase (AdjP), and a preposition a prepositional phrase (PP). Many grammatical frameworks use determiner phrase (DP) for phrases headed by a determiner, such as the curious child; others use NP for similar examples.

Phrases may include complements, which complete or are selected by the head, and modifiers, which add information. In read the book carefully, the book is a complement of read, while carefully modifies the reading event. Phrase structure represents these groupings rather than treating every word as equally related to every other word.

A simplified bracketed analysis of The curious child opened the box shows how phrases can be nested:

In this analysis, the curious child is one phrase and the box another; the verb and its object form a larger VP. Exact labels and details vary among syntactic theories, but representing nested structure helps explain why some word sequences behave as units.

Clauses and recurring patterns

A clause typically contains a predicate and its associated participants. A sentence may consist of one clause or combine several. Clauses can be joined by coordination, as in The child opened the box and the adult read the note, or one clause can be embedded within another, as in The child said that the box was open.

Phrase-structure rules are one way to state recurring patterns. For example, a simplified English clause may contain a subject phrase followed by a predicate phrase. Such rules describe patterns; they do not establish a universal word order for all languages.

Functions and meaning in clauses

Grammatical relations describe how phrases function in a clause. Common relations include:

• Subject: Often the phrase that controls agreement or occupies a characteristic clause position.

• Object: A phrase associated closely with a verb; languages may distinguish direct and indirect objects.

• Oblique: A phrase, often introduced by an adposition or marked by case, that expresses a relation such as location, source, or recipient.

The ways these relations are identified differ across languages. Word order, case marking, agreement, and other grammatical patterns can signal them. In English, word order is especially important: in The dog chased the cat, the dog is the subject and the cat the object.

Grammatical relations are not the same as semantic roles, which describe a participant’s meaning-related role in an event. A subject is often an agent, but not always. In The window was broken by the wind, the window is the grammatical subject, although it is affected by the event rather than causing it. Syntactic function and event meaning must therefore be analyzed separately.

A method for syntactic analysis

Use a sequence of checks to analyze an unfamiliar sentence:

1. Identify its words and likely categories from their form and use.

2. Look for possible constituents, testing them with substitution, movement, questions, or coordination where appropriate.

3. Group constituents into phrases and identify each phrase’s head.

4. Determine how the phrases relate within the clause—for example, which is subject, object, or oblique.

5. Check that the proposed structure accounts for the sentence’s word order and grammatical patterns. If more than one structure is possible, consider whether the sentence is structurally ambiguous.

For example, The child opened the box with a key can be analyzed with with a key as a modifier of the opening event: the child used a key. In another context, a phrase of this kind may describe an instrument or modify a noun. Syntactic grouping makes these possible relationships explicit.

Putting the concepts together

Syntax examines the hierarchical organization of words into phrases and clauses. Constituency tests provide evidence about which words form units, heads organize phrases, and grammatical relations describe how phrases function in clauses. Because individual tests have limitations and grammatical relations do not simply equal semantic roles, sound syntactic analysis draws on multiple kinds of evidence.