Copular or linking verbs

We have already learned that intransitive verbs do not take objects.
Examples are: sleep, sit, rest, weep, laugh, cry etc.

She is weeping.

The child sleeps.

The boy was laughing.

There is yet another variety of verbs which do not normally take objects. These are called copular verbs or linking verbs. While intransitive verbs make complete sense on their own, copular verbs require a word or phrase to make their meaning complete.
Consider the example given below.

She is….

As you can see this sentence does not make complete sense. To make it complete we need to supply a word or a phrase. The word or phrase thus added at the end of a sentence to make its meaning complete is called a complement. And the verb which joins a subject with its complement is called a copular or linking verb.
When this word/phrase refers to the subject, it is called a subject complement. When it refers to the object, it is called an object complement. The linking verb is also called a verb of incomplete predication.
The most common copular verbs are: act, be, become, feel, appear, grow, taste, sound etc.
Copular verbs do not normally take an object. But sometimes these verbs may be used transitively.
Examples are given below.

She acted well. (Copular use)

She acted her part well. (Transitive use)

I am feeling unwell. (Copular use)

The doctor felt the patient’s pulse. (Transitive use)

The proposal sounds interesting. (Copular verb)

The general sounded the bugle. (Transitive verb)

The boy has grown taller. (Copular verb)

The farmers grow vegetables.. (Transitive verb)

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