Grammatical Summary

THE STRUCTURE OF THE PASSIVE VOICE

As previously stated, the passive voice in English is formed by combining a form of the verb to be with the past participle of a transitive verb. Its overall structure and its contrast with the active voice is probably easier to see if they are displayed in a paradigm of traditional English verb tenses.

Simple Tenses

Active Voice	Passive Voice
to stop	to be stopped
I stop	I am stopped
I stopped	I was stopped
I will stop	I will be stopped
I would stop	I would be stopped
to have stopped	to have been stopped
I have stopped	I have been stopped
I had stopped	I had been stopped
I will have stopped	I will have been stopped
I would have stopped	I would have been stopped

Theoretically, passive voice constructions can appear in any tense, but in actual practice with "progressive tense forms," they seem to be confined mostly to the present and past tenses. (Progressive tense forms involve the verb be plus a main verb in -ing.)

Progressive Tenses

Active Voice	Passive Voice
I am stopping	I am being stopped
I was stopping	I was being stopped

Modal Auxiliary Verbs

Passive voice constructions can also be used with "modal auxiliary verbs" (can, might, etc.), such as in the following examples:

Active Voice	Passive Voice
I can stop	I can be stopped
I could stop	I could be stopped
I may stop	I may be stopped
I might stop	I might be stopped
I must stop	I must be stopped
I should stop	I should be stopped

Notice that the passive voice constructions always appear after the modal auxiliary verbs.

Summary of Definition of Passive Voice

1. A passive voice construction contains a form of the verb to be (or to get) plus a past participle of a transitive verb.

2. It expresses an action carried out on the subject of the sentence.