Not mentioning the agent

In most passive sentences we have no interest in who or what performs the action. We are interested in the action itself, who or what is affected by the action, or what is the result of it (see Overview). In fact, only about 20% of passive sentences mention the agent:

That window has been broken again!

Mentioning the agent

We mention the agent when we think the information is important, especially if we want to say more about it, for example with a relative clause:

I remember being taken to the fair by my father, who rarely showed any interest in such things.
The survivors were picked out of the water by a cruise liner which had heard their distress call.

• The agent is usually introduced with by

(See Section 6.3 for prepositions after passives).

Verbs that have two objects (usually a person and a thing) in the active usually have two passive forms because either of the objects can become the new subject:

They gave the award to an unknown actress.
(= active)
The award was given to an unknown actress.
(= passive)
An unknown actress was given the award.
(= passive)

• We usually add a preposition before the personal object. The preposition is usually to, but we sometimes use for:

A note was handed to the minister.
A slice of cake was cut for him.

• However, some verbs, e.g. allow, ask, cause, forgive, deny, don't normally take a preposition before the personal object:

Permission was refused him.

We can't use some verbs as freely in the passive as others.

• We can't use intransitive verbs in the passive because they don't have an object that can be changed into the subject:

The Tasmanian tiger was died out early this century. - INCORRECT
The Tasmanian tiger died out early this century. - CORRECT

• Some verbs, e.g. suggest and explain, can't change the indirect object to subject:

He was explained the procedure. - INCORRECT
We were suggested a new time. - INCORRECT
The procedure was explained to him. - CORRECT
A new time was suggested for us. - CORRECT

• Some verb phrases with two objects can't be passive at all:

I bear him no ill will.
The book earned him a fortune.
Let me wish you luck.

• Some verbs are followed by two nouns, but the second is not really an object. We can see this if it is replaced by an adjective:

They declared him President.
He was declared President.
The doctor declared him dead.
He was declared dead.