TRANSITIVE VERBS (verbs that take an object) can be used in two ways, or ‘voices’: active and passive:
ACTIVE: The dog bit him.
PASSIVE: He was bitten by the dog.
Transitive verbs usually describe some kind of action. In the sentence The dog bit him, you have a person, thing, or idea that performs the action and one that is affected by it. The first is the subject The dog and the second the object him. When we put a sentence into the passive voice, the object him becomes the subject He. The original subject The dog becomes the agent and has the preposition by placed in front of it. In everyday writing the active voice is much more common than the passive.
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