Words that tell what the subjects do in sentences are called action words or verbs.
Examples:
Susan, boys, mother, and children are the subjects in the above sentences.
The words walks, fly, cooks, and run tell what the subject does.
These words show action.
Words that show action are called verbs.
A verb brings life to a sentence by telling what the subject does.
Verbs are the most important words in a predicate.