Types of sentences in the passive voice.
1. We form positive sentences by putting the verb form on the second place:
SUBJECT + TO BE + PAST PARTICIPLE
The furniture has been delivered.
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2. We form questions by putting the verb to be before the subject.
Is your car being serviced?
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3. We form negative sentences by putting not after to have or to be.
The office has not been cleaned yet.
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4. You should form the passive of infinitives like this:
VERB + TO BE + PAST PARTICIPLE
He wants to be given a pay-rise.
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5. You should form the passive of modal verbs like this:
MODAL VERB + PAST PARTICIPLE
The roof must be repaired as soon as possible.
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