What are complements?

The label complement is applied to several different things.
A subject complement
A subject complement is a word or phrase which follows a copular verb. It either modifies the subject or denotes something identical to the subject.
The bold italic items in the following sentences are examples of subject complements.

• Jane is an advocate.
• Susie became a travel writer.
• I am very excited.
• Alice is in the office.

Object complement
An object complement is a phrase which follows a direct object. An object complement either modifies the object or denotes something identical to it.

• I consider hang-gliding dangerous.
• They appointed him monitor.

The complement of an adjective or a noun is a word or phrase which directly follows it.
Read the following sentences:

• He is fond of his grand children. (Here the phrase ‘of his grand children’ is the complement of the adjective fond.)
• Let’s get a bottle of wine. (Here the phrase ‘of wine’ is the complement of the noun bottle.)

Notes
The complement of a preposition is the same as the object of a preposition.

• The cat is on the roof. (Here the phrase ‘the roof’ is the complement of the preposition on. It is also the object of the preposition on.)

The complement of a verb is the same as the object of a verb.

• Jane bought a new car. (Here the phrase ‘a new car’ is the complement of the verb bought. It is also the object of the verb bought.)

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