A predicative adjective is a word that describes a noun, but occurs nearer the predicate of a sentence. Put simply, it is a describing word that gives more information about a noun or pronoun, even though it appears on the other side of a verb. It is frequently referred to as a predicate adjective. Typically, identifying a predicative adjective is much simpler than it might appear.
For example, in the sentence, "The beach was sandy," the word sandy describes the noun beach. It tells more about the beach. The word sandy, therefore, is an adjective. Even though the words sandy and beach are separated by a verb, it is still clear that the two are related; one word describes the other.
The verb that separates them, the word was, is the predicate of the sentence. It is a linking verb that shows the action of the noun beach. This is why the word sandy is called a predicative adjective. It is an adjective that is separated from its noun and also completes the meaning of the predicate in the sentence.
It can be important to keep in mind that the predicate in a sentence is an action word – a verb or verb phrase. A noun is a person, place, or thing and most often is the subject of a simple sentence. Adjectives are words that describe nouns. Predicative adjectives describe and enhance the meaning of both the predicate and the noun.
In the sentence, "The sky is turning dark," the word dark is the adjective that describes, or modifies, the word sky. The predicate, is turning, separates the words sky and dark. Thus, dark is the predicative adjective.
The same information can be explained in more advanced terms, as well. In English grammar, a complement is anything that completes the meaning of a clause, phrase, or sentence. A modifier is anything that is added to alter the meaning of a word. When adjectives are used with nouns, they can change, or modify, the meaning in subtle ways. This is why adjectives are called modifiers.
Either set of terms is appropriate to describe a predicative adjective. The word dark in the sentence above is the complement of is and the modifier of sky. The word sandy in the sentence above is the complement of the verb was and the modifier of the word beach. In grammatical terms, then, a predicative adjective is the complement of the predicate, but its function is really to modify the subject of the sentence. It does not matter which terms are used, as long as the correct words can be identified and explained.