Syntax

Adjunct

A word or word group that qualifies or completes the meaning of another word, and is not itself a main structural element in a sentence.

Affix

A type of morpheme that must be attached to a head and cannot be used independently.

Agent

The semantic role of a person or thing that is the doer of an event.

Auxiliary

A verb that provides grammatical information not given by the main verb of a sentence.

Base position

The function where a moving element originates and where its lowest function is realized.

Binary branching

A hypothesis where every branch of meaning consists of at most two elements.

Clause

A sentence that is part of another sentence, including main and subordinate clauses.

Co-ordination

Joining elements using 'and' or 'or', which corresponds to a single node in the branching system.

Complement

A unit that is subordinate to the head, also known as the 'sister of a head'.

Complementizer

A type of morpheme that introduces a clause and determines grammatical information.

Constituent

A unit of meaning that corresponds to a node and can be coordinated, moved, or elided.

Constituent (wh-) question

A type of question asking about the identity of a participant of an event, opposite of yes/no questions.

Constituency tests

Tests for determining constituents, including pronominalisation, movement, coordination, and ellipsis.

Direct object

A grammatical role signifying a noun phrase that receives the action of a transitive verb.

Economy (movement)

The principle that movement should be as short as possible and move the smallest constituent possible.

Ellipsis

The omission of elements that are understood from the context of a sentence.

Expletive (subject)

A word or phrase that fills out a sentence without referring to any entity.

Floating quantifier

A separable morpheme that is detached from the noun and associates with it.

Head

The part of a constituent that has certain properties and determines the meaning of the whole.

Head movement

Movement of a head, usually triggered by the need to place an affix.

Movement

The description of structures where a single element has two functions.

Passivization

A construction type where the agent is removed or less prominent, and the patient becomes the subject.

Pronoun (replacement)

A test used to determine constituency by replacing a noun with a pronoun.

Relative clause

A clause that modifies a noun, e.g., 'A person that I met'.

Subject

A grammatical role corresponding to a noun phrase in the nominative case.

Subject auxiliary inversion

A structure used in questions where the auxiliary verb precedes the subject.

Thematic role = semantic role

The underlying relationship a participant has with the main verb in a clause.

Transitive verb

A verb that has both an agent and a patient and requires a direct object.

Intransitive verb

A verb that does not require a direct object, often involving only a subject and an action.