A clause is the smallest constituent that can express a proposition.

For example, "Alice arrived" or "Socrates is a man."


1   Etymology

from Medieval Latin clausa "conclusion," used in the sense of classical Latin clausula "the end, a closing, termination," also "end of a sentence or a legal argument," from clausa, fem. noun from past participle of claudere "to close, to shut, to conclude"

2   Form

A clause essentially consists of a subject and a predicate.

3   Properties

4   Classification

4.1   Independent & Dependent

A clause is independent (= root = main) if it constitutes a statement otherwise it is dependent (= subordinate = embedded). For example, "Socrates is a man" is an independent clause, but "is a man" is dependent.

There are three types of embedded clauses: specifier clauses, complement clauses, and adjunct clauses.

4.1.1   Specifier clause

Specifier clause (serve as the subject of a sentence):

[[People selling their stocks] caused the crash]

[[For Mary to love John] is a travesty]

That Bill loves chocolate is likely.


4.1.2   Complement clause

Complement clause (siblings to the verb):

Alice said [that Bob loves dogs]

Alice asked [if they could help]


4.1.3   Adjunct clause

Adjunct clause:

[The man [that I saw get into the cab]] robbed the bank

[The car [that just turned the corner]] was his.

The relative clause "I saw get into the cab" modifies the head man. (Relative clauses may appear to lack an overt subject)

An adjective clause is a dependent clause that modifies a noun.

For example:

The musician who wrote this song is Canadian.

Jason bought our hybrid car, which will help him save on gas.

The musician that wrote this song is Canadian.

4.2   Finite & Non-finite

A finite (= tensed) clause is a clause with a predicate that is tensed; contains a structurally central finite verb; bears a tense feature (e.g. +/- past or +/- future); takes "if" or "that" as a complementizer; takes nominative case:

I might do so

I can do so

I could do so

I should do so

I would do so

I will do so

I said that I did so

I said that you did so

I said that he did so

I said that we did so

I said that they did so

I wonder if he did so

I believe he did so

I promise that he did so

I know that I will do so

I think that he will do so

A non-finite (= infinitival = tense-less) clause is a clause that contains a structurally central non-finite verb; takes "for" as a complementizer; takes accusative case.

You want me to do so

I want you to do so

I want you doing so

I want him to do so

I want us to do so

I want them to do so

I would like for them to do so

I asked for him to do so

I saw him do so

I have never seen them do so

It is easy for us to do so

Him doing so was a big disappointment

For him to have done so is a travesty

Having do so, we did so


  • Finite clauses can contain auxiliaries and modals as tense, but non-finite clauses can only take "to".

    I think he will eat apples

    I want him to eat asparagus

x Finite Infinite
Tense mutable immutable
Agreement S-V agreement no S-V agreement
Case nominative accusative
C that, if for
T should, would infinitival 'to'

4.3   Restrictive & Unrestrictive

A restrictive clause is a clause that restricts some other part of the sentence.

A nonrestrictive clause is a clause that can be left out without changing the meaning of the sentence.

Example: "that sparkle" is a restrictive clause. Example: "which are expensive" is a nonrestrictive clause.

Note: Commas usually surround nonrestrictive clauses.

Example: "Diamonds, which are expensive, often elicit forgiveness."

'That' indicates a clause which is essential to the meaning of the sentence.

Lisa worse the sandals that she bought in Italy.

'Which' introduces a clause that gives secondary, non-essential information.

Lisa worse the sandals, which she bought in Italy.

5   Predicative Expression

A predicative expression (or just predicative) is (part of) a clause predicate. The term is used more specifically to denote expressions that typically follow a copula (= linking verb), e.g. be, seem, appear, or that appear as a second complement of a certain type of verb, e.g call, make, name, etc.[1] The most frequently acknowledged types of predicative expressions are predicative adjectives (also predicate adjectives) and predicative nominals (also predicate nominals).

6   Predicate modifier

Syntactically, there are many kinds of predicate modifiers.

Example: "He speaks glibly, with a forked tongue, and sometimes tongue in cheek." Example: "He is a diplomat, he is a two face diplomat, he stoops at nothing, he stoops to conquer, by fair means or foul."

These example show predicate modified by:

In general syntax, we recognize a special class of functors, the predicate modifiers, which turn predicates into predicates. In an extended but practical usage, we may call them adverbs.

We cannot replace predicates with coextensive predicates withing adverbial contexts and preserve truth.

Example: Suppose those who drive are exactly those who walk. It does not follow that those who drive slowly, walk slowly.