The Passive:

The passive is formed by using the verb 'be' in the correct form with the past participle of the main verb of the sentence. The verb 'be' may be in a tense, such as the present perfect, or it may be some other form of the verb, such as the full infinitive. We normally put the person/thing the action is done to before the verb, and the person/thing doing the action after the verb (when it is necessary). Here are examples of different forms of the passive.

1. Our mail is delivered every morning. (present simple)
   
2. David is being told off by the Head. (present continuous)
   
3. The tickets were booked by a travel agent. (simple past)
   
4. We did some shopping while our car was being washed. (past continuous)
   
5. My wallet has been stolen! (present perfect)
   
6. I had been invited to the party, but I didn't go.  (past perfect)
   
7. An announcement will be made when we have more information. ('will' future)
   
8. All compositions should be left on my desk at the end of the lesson. (other modals)
   
9. I can't stand being insulted in public like that! (-ing form)
   
10. Terry refused to be interviewed by the local newspaper. (full infinitive)
    

Note: We do not normally use the passive in the present perfect continuous or the past perfect continuous.

We use the passive :

• when we don't know who does/did/etc the action. My car has been stolen!
• when we aren't interested in who does/did/etc the action. The monkeys are fed every day at three.
  
• when it's obvious who does/did/etc the action. A man was arrested last night in a local park.
• for emphasis, formality and impersonal style. Passengers will be informed of any delay as soon as possible.

Some verbs can take two objects: a direct object and an indirect object. My doctor gave me a prescription. In the passive, we usually use the person as the subject.

• I was given a prescription (by the doctor).

When we want to say who did the action, we normally use by. The burglar was spotted by a neighbour.

Note: we usually say who does/did/etc an action only when it is necessary.

When we want to describe something used to do an action, we normally use with.This rope has been cut with a knife.

Note: some verbs are not normally used in the passive. They include intransitive verbs (without objects), eg disappear, vanish, consist, seem, appear, and some common transitive verbs such as have, let, lack, resemble, fit and suit.

Note: when an adjective is followed by a full infinitive, we do not normally use the passive.