The use of the passive voice

The passive voice is more common in formal written English. It is often used in newspapers, academic and scientific writing, and reports, which attempt to be less personal. Most passive sentences do not have an agent, as the focus of the sentence is not on the doer of the action but on its recipient. As a rule, the agent is only mentioned in the passive sentence if it is important new information which cannot be omitted:

The Lord of the Rings was written by J. R. R. Tolkien.
While Tony was walking home last night, he was mugged by a group of young men, who stole his mobile phone and wallet.

The passive voice is preferred over the active in the following cases:

Change of focus

We use the passive voice when we want to shift the focus of attention from the agent to the recipient of the action. If the agent is not important information, it is usually omitted in the passive sentence:

The flood killed 24 people. (focus on the flood, the agent)
24 people were killed by the flood. (focus on 24 people, the recipient)

The water in the nearby pool reflected her figure. (focus on the water in the nearby pool, the agent)
Her figure was reflected in the nearby pool. (focus on her figure, the recipient)

Unknown or unimportant agent

We use the passive voice when we do not know who is performing the action or if the identity of the agent is not important. In this case the agent is omitted in the passive sentence:

Tom's bike has been stolen. (unknown agent)
I was advised to apply for a visa in advance. (unimportant agent)

Generalised agent

We use the passive voice with a generalised agent, i.e. when the subject of the active sentence is you, one, we, people, everybody etc.:

The Venus de Milo can be seen at the Louvre. (You can see the Venus de Milo at the Louvre.)
Smart phones are used for many different things. (We/People use smart phones for many different things.)

Obvious agent

We use the passive voice when the identity of the agent is obvious. In this case the agent is usually omitted in the passive sentence:

The murderer has been arrested. (The police have arrested the murderer.)

Impersonality

We use the passive voice when we do not want to mention the agent because

• we want to avoid naming the specific person responsible for the action,
• we want to sound objective or tactful without revealing the source of information or
• it would be inappropriate or embarrassing to mention the agent:

It has been decided to cancel next week's meeting.
I regret to inform you that your application has been rejected.
Mistakes have been made.

Description of processes

We often use the passive voice in describing processes, when the emphasis is on the actions and not on the people who perform them. The agent is usually omitted:

Then the pig is disembowelled and cut into two.
After they had been picked, the grapes were crushed with bare feet.