Use of Passive
Passive voice is used when the focus is on the action. It is not important or not known, however, who or what is performing the action.
Example: My bike was stolen.
In the example above, the focus is on the fact that my bike was stolen. I do not know, however, who did it.
Sometimes a statement in passive is more polite than active voice, as the following example shows:
Example: A mistake was made.
In this case, I focus on the fact that a mistake was made, but I do not blame anyone (e.g. You have made a mistake.).
Form of Passive
Subject + finite form of to be + Past Participle
Example: A letter was written.
When rewriting active sentences in passive voice, note the following:
- the object of the active sentence becomes the subject of the passive sentence
- the finite form of the verb is changed (to be + past participle)
- the subject of the active sentence becomes the object of the passive sentence (or is dropped)