Adjective Complement

What Is an Adjective Complement?

An adjective complement is a phrase or a clause that completes the meaning of an adjective. For example:

• Anna was angry about your comment.
(The highlighted phrase is an adjective complement. It completes the meaning of the adjective "angry.")
• Anna was angry that you commented.
(The highlighted clause is an adjective complement. It also completes the meaning of the adjective "angry.")

Types of Adjective Complement

An adjective complement can take one of three forms: (1) a prepositional phrase, (2) an infinitive phrase, or (3) a clause.

(1) Adjective Complements as Prepositional Phrases

• John is happy with his test results.
• I am worried about her attitude.
• Sarah felt alone in the world.

In every example on this page, the adjective complement is shaded, and the adjective it completes is in bold. Notice that these adjective complements are headed with prepositions ("with," "about," and "in"), making them prepositional phrases. Read more about prepositional phrases.

(2) Adjective Complements as Infinitive Phrases

• We were happy to be of service.
• The crew were relieved to reach dry land.
• Are you ready to go?

Notice that these adjective complements are headed with infinitive verbs ("to be," "to reach," and "to go"), making them infinitive phrases. Read more about infinitive phrases.

(3) Adjective Complements as Clauses

• I am unsure why you raised this point.
• She was suspicious how you passed the test.
• John seems certain who contacted the media.
• Anna was disappointed that you promoted Sarah.

A clause that functions as an adjective complement is headed by:

• An interrogative pronoun (e.g., "who," "what," "which," "whose")
• An interrogative adverb ("why," "where," "when," "how")
• "That."

Like all clauses, it has a subject and verb. From a structural perspective, an adjective-complement clause looks like a noun clause, but it is classified as a restrictive adverbial clause because it provides essential information about the adjective it modifies.

Note: If the clause modifies the verb, it is not an adjective complement. In these two examples, the clauses are not adjective complements because they modify verbs (underlined).

• I was wrong when I predicted the weather.
• The CEO was anxious when the tax inspector called.

This point causes confusion, even among grammarians.

Traits of an Adjective Complement

• An adjective complement is a phrase or a clause, not a single word.
• An adjective complement follows immediately after the adjective it completes.
• An adjective complement modifies a predicate adjective.
• An adjective complement is necessary to complete the meaning of its adjective.

A predicate adjective is an adjective that follows a linking verb and modifies (i.e., describes) the subject of the linking verb. For example:

• John was angry about my promotion.
(In this example, "was" is a linking verb. It links the subject "John" to the predicate adjective "angry." The phrase "about my promotion" is an adjective complement modifying "angry.")
• Sarah seems unconcerned that she was overlooked.
(Here, "seems" is a linking verb. It links the subject "Sarah" to the predicate adjective "unconcerned." The clause "that she was overlooked" is an adjective complement modifying "unconcerned."

Read more about predicate adjectives.

Why Adjective Complements Are Important

Complements are important because they are essential for meaning. This is the difference between complements and normal modifiers. (Modifiers can be removed from a sentence without breaking the meaning.) Looks at these examples:

• I am extremely satisfied on my own.
(In this example, "extremely" an adverb modifying the adjective "satisfied." If it is removed from the sentence, the meaning is not lost. "On my own," however, is a prepositional phrase that complements "satisfied." If it is removed, the reason for saying the sentence is lost.)

• We are a little unsure why you are here.
(Here, "a little" is an adverbial phrase modifying the adjective "unsure." If it is removed, the meaning is not lost. The clause "why you are here " is an adjective complement. If it is removed, the essence of the sentence is lost.)

Key Points