Passive - Use
We only use the passive when we are interested in the object or when we do not know who caused the action.
Example: Appointments are required in such cases.
We can only form a passive sentence from an active sentence when there is an object in the active sentence.
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Form
to be + past participle
How to form a passive sentence when an active sentence is given:
- object of the "active" sentence becomes subject in the "passive" sentence
- subject of the "active" sentence becomes "object" in the "passive" sentence" (or is left out)
Active: Peter builds a house.

Passive: A house is built by Peter.

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Examples
Active: Peter builds a house. (Simple Present)

Passive: A house is built by Peter.

Active: Peter built a house. (Simple Past)

Passive: A house was built by Peter.

Active: Peter has built a house. (Present Perfect)

Passive: A house has been built by Peter.

Active: Peter will build a house. (will-future)

Passive: A house will be built by Peter.

Active: Peter can build a house. (Modals)

Passive: A house can be built by Peter.
We have listed active and passive forms in the following examples:
We used the phrase I drive and have put this phrase into most common tenses.
Active (Simple Forms):
Simple Present: I drive
Simple Past: I drove
Present Perfect: I have driven
Past Perfect: I had driven
will-future: I will drive
Future Perfect:I will have driven
Conditional I: I would drive
Conditional II: I would have driven

Active (Progressive/Continuous Forms):
Simple Present: I am driving
Simple Past: I was driving
Present Perfect: I have been driving
Past Perfect: I had been driving
will-future: I will be driving
Future Perfect: I will have been driving
Conditional I: I would be driving
Conditional II: I would have been driving

Passive (Simple Forms):
Simple Present: I am driven
Simple Past: I was driven
Present Perfect: I have been driven
Past Perfect: I had been driven
will-future: I will be driven
Future Perfect: I will have been driven
Conditional I: I would be driven
Conditional II: I would have been driven

Passive (Progressive/Continuous Forms):
Present: I am being driven
Past: I was being driven
Present Perfect : I have been being driven
Past Perfect : I had been being driven
Future : I will be being driven
Future Perfect : I will have been being driven
Conditional I : I would be being driven
Conditional II : I would have been being driven