1. Some verbs have a meaning that is complete in itself. Such a verb needs only a subject. When this has been supplied, we have a sentence, for the mere verb, without any additional word or words, is capable of being a predicate.
1. Birds fly.
2. Fishes swim.
3. The sun shines.
4. The moon rose.
5. The man scowled.
6. The girl laughed.
7. The owls hooted.
8. The clock ticked.
Verbs of this kind are sometimes called complete verbs or verbs of complete predication.
2. Other verbs are not, by themselves, capable of serving as predicates. Thus…..
1. The Indians killed ——.
2. Mr. Harris makes ——.
3. Tom is ——.
4. The man seemed ——.
These are not sentences, for the predicate of each is unfinished. The verb requires the addition of a substantive or an adjective to complete its sense.
1. The Indians killed deer.
2. Mr. Harris makes shoes.
3. Tom is captain.
4. The man seemed sorry.
Verbs of this kind are often called incomplete verbs or verbs of incomplete predication.
Note : The meaning of the verb determines to which of these classes it belongs. Accordingly, the same verb may belong to the first class in some of its senses and to the second in others.
A substantive or adjective added to the predicate verb to complete its meaning is called a complement.
Complements are of four kinds - the direct object, the predicate objective, the predicate nominative and the predicate adjective.
In the above examples, deer and shoes are direct objects - the former denoting the receiver of the action, the latter denoting the product. CAPTAIN is a predicate nominative, denoting the same person as the subject Tom. SORRY is a predicate adjective describing the subject man.
Complements may, of course, be modified. If they are substantives, they may take adjective modifiers; if adjectives, they may take adverbial modifiers.
For convenience, the definitions of the four kinds of complements are here repeated, with examples.