Chapter 16

Linguistics: Syntax, Semantics & Phonology

College

Linguistics studies language as a formal system rather than a set of style rules. This chapter introduces three of its core branches — the structure of sentences, the nature of meaning, and the sound system of English — with the analytical tools linguists actually use.

At a glance
Core ideaLinguistics studies language as a formal system, not a set of style rules.
Key termsSyntax (structure), semantics (meaning), phonology (sound); phoneme vs allophone.
You can…Apply constituency and entailment tests to expose hidden structure.
Watch outLinguistics is descriptive, not prescriptive — it studies rules, not “correctness.”
Theory

Syntax: the generative view

Where school grammar labels words, syntax as a discipline models the rules that generate every grammatical sentence of a language from a finite set of principles — and rules out every ungrammatical one. Noam Chomsky's key observation was that speakers can judge grammaticality independent of meaning: "Colorless green ideas sleep furiously" is nonsensical but perfectly grammatical, while "Furiously sleep ideas green colorless" is neither. This showed syntax to be an autonomous system, not merely a byproduct of semantics.

Modern syntax represents sentences as hierarchical phrase structure trees, built from constituents that can be moved, replaced, or coordinated as single units. A phrase like the very old book behaves as one unit — it can be replaced wholesale by it — which is the operational test for constituency.

Semantics: how meaning is built

Semantics studies literal, context-independent meaning. Central concepts include sense (a word's meaning within the language system) versus reference (what it points to in the world); entailment (if A is true, B must be true — "It's a dog" entails "It's an animal"); and compositionality, the principle that a sentence's meaning is built systematically from its parts and their arrangement.

Phonology: the sound system

Phonology studies how sounds pattern within a language, distinct from phonetics (the physical production of sound). A phoneme is the smallest sound unit that changes meaning: swap the first sound of pat for the first sound of bat and the word changes — /p/ and /b/ are separate phonemes in English. Sounds that don't change meaning when swapped, like the two slightly different English "p" sounds in pin and spin, are allophones of one phoneme.

S NP Det N The dog VP V NP chased Det N the ball
A syntax tree shows how "the dog chased the ball" is built from nested noun and verb phrases.
Explanation

The unifying idea across all three branches is that native speakers hold implicit, systematic knowledge they cannot fully articulate but apply flawlessly. No one taught you the rule that "the big red barn" is acceptable but "the red big barn" is not (adjective ordering follows a covert hierarchy: opinion, size, age, shape, colour, origin, material). Linguistics makes that tacit competence explicit and testable.

This is also why linguistics is descriptive, not prescriptive — unlike a style guide, it does not judge "ain't" or double negatives as wrong; it studies them as rule-governed features of the dialects that use them (African American Vernacular English's negative concord, for instance, follows strict internal rules, just different ones from Standard English).

Ambiguity as evidence

"Flying planes can be dangerous" is genuinely ambiguous — it could mean piloting is dangerous, or that planes in flight are dangerous. This is not sloppy writing; it is structural ambiguity, where one string of words maps onto two different underlying tree structures. Ambiguity is one of the linguist's best diagnostic tools for revealing hidden structure.

Practical

Exercise: constituency and entailment tests

Constituency test

Sentence: "The student with the red backpack answered the question."

Substitution test: replace "the student with the red backpack" with "she" — the sentence still works ("She answered the question"), proving the whole phrase is a single constituent (a noun phrase), not just a loose sequence of words.

Movement test: "It was the question that the student with the red backpack answered" — the object phrase can be fronted as a unit, confirming its constituent status.

Entailment test

Claim A: "Priya ran to the store." Claim B: "Priya moved." Does A entail B? Yes — if A is true, B must be true in every possible situation, so this is a valid entailment. Contrast with "Priya ran to the store" and "Priya was tired," which is merely a plausible implicature, not a guaranteed entailment — she could have run without being tired.

Now you try: apply the substitution test to "The book on the shelf by the window is mine" to isolate its subject noun phrase, and decide whether "John bought a car" entails "John owns a car" (it does not — he might have bought it as a gift).

Q&A
How is syntax different from traditional school grammar?

ASchool grammar is largely prescriptive and classificatory — it labels words as nouns or verbs and states rules of correctness. Syntax as a linguistic discipline is a formal, predictive model: it aims to specify the finite rule system that generates every grammatical sentence a speaker will ever produce or accept, including sentences never previously heard. It treats grammaticality (well-formedness) as separate from meaningfulness and from social correctness.

What is the difference between phonetics and phonology?

APhonetics is the physical study of speech sounds — how the tongue, lips, and vocal cords produce them, and how they can be measured acoustically. Phonology is the abstract, cognitive study of how a specific language organises those sounds into a system of contrasts. Two languages can share the same physical sound (phonetics) but treat it completely differently in their sound system (phonology) — English treats /r/ and /l/ as separate phonemes, while Japanese phonology treats them as one.

What does "compositionality" actually explain?

AIt explains how a finite vocabulary and a finite set of rules produce infinite meaningful sentences — you have never seen most of the sentences you understand today, yet you understand them instantly because their meaning is computed systematically from the meanings of their parts and how those parts are combined. It also explains why word order changes meaning: "the dog bit the man" and "the man bit the dog" use identical words but combine them differently, yielding opposite meanings.

Are idioms a problem for compositionality?

AYes, genuinely — "kick the bucket" does not mean literally striking a pail; its meaning ("to die") cannot be computed from its parts. Linguists treat idioms as effectively single lexical units stored whole in the mental dictionary, an exception that proves the rule: compositional rules apply to ordinary phrases, while idioms are memorised chunks that happen to look like phrases.

Concept mind map

How the ideas connect

Every key idea in this chapter, branching from the core concept — use it to see the whole picture at a glance.

PhonologyMorphologySyntaxSemanticsPhonemeConstituencyGenerative grammarLinguistics
Infographic

The key facts, visualised

Phonology
the sound system and patterns of a language
Syntax
the rules governing how words combine into sentences
Semantics
the study of linguistic meaning
Phoneme
the smallest sound unit that distinguishes meaning
Solved examples

Worked problems, step by step

Follow each solution line by line, then try to reproduce it on paper before moving on.

Example 1Use a constituency test to show "the old man" is a unit in "The old man left."

  1. A constituent can usually be replaced by a single pronoun.
  2. Replace "the old man" with "he": "He left." remains grammatical.
  3. The successful substitution shows the phrase is one syntactic unit.

Example 2Explain how "bat" and "pat" show that /b/ and /p/ are separate phonemes.

  1. The two words differ in only one sound at the start.
  2. That single change alters the meaning of the word.
  3. A minimal pair like this proves the sounds are distinct phonemes.
Practice problem set

Now you try

Work each one out first, then tap to reveal the worked answer.

1What is morphology?
The study of word structure and how morphemes combine to form words.
2What is a minimal pair?
Two words differing in a single sound that changes meaning, like "ship" and "sheep".
3What does syntax study?
The rules by which words are ordered and combined into grammatical sentences.
4What is the difference between semantics and pragmatics?
Semantics is literal meaning; pragmatics is meaning in context, including implication.
5What does generative grammar aim to describe?
A finite set of rules that can generate all and only the grammatical sentences of a language.