Passive tense

The passive voice is a grammatical "voice". The noun or noun phrase that would be the object of a corresponding active sentence (such as "Our troops defeated the enemy") appears as the subject of a sentence or clause in the passive voice ("The enemy was defeated by our troops").

The subject of a sentence or clause featuring the passive voice typically denotes the recipient of the action (the patient) rather than the performer (the agent). Verbs in the passive voice in English are formed using several parts (periphrastically): the usual construction uses the auxiliary verbs to be or to get together with the past participle of the main verb.

For example, Caesar was stabbed by Brutus is in the passive voice. The subject, Caesar, indicates the person acted upon. The agent is expressed here with the phrase by Brutus, but this can be omitted. The equivalent sentence in the active voice is Brutus stabbed Caesar, in which the subject denotes the doer, or agent, Brutus. A sentence featuring the passive voice is sometimes called a passive sentence, and a verb phrase in passive voice is sometimes called a passive verb.

English allows a number of passive constructions which are not possible in many of the other languages with similar passive formation. These include promotion of an indirect object to subject (as in Tom was given a bag) and promotion of the complement of a preposition (as in Sue was operated on, leaving a stranded preposition).

Use of the passive in English varies with writing style and field. It is generally much less used than the active voice but is more prevalent in scientific writing than in other prose. Contemporary style guides discourage excessive use of the passive but appropriate use is generally accepted, for instance where the patient (the undergoer, target, or recipient of the action) is the topic, the agent is unimportant (and therefore omitted), or the agent is to be highlighted (and therefore placed toward the end).

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