In English, the passive voice is marked by using be or get followed by a past participle. For example: The enemy was defeated. Caesar was stabbed. The recipient of a sentence's action is referred to as the patient. In sentences using the active voice, the subject is the of the action—referred to as the agent. Above, the agent is omitted entirely, but it may also be included adjunctively while maintaining the passive voice: The enemy was defeated by our troops. Caesar was stabbed by Brutus. The initial examples rewritten in the active voice yield: Our troops defeated the enemy. Brutus stabbed Caesar. The English passive voice typically involves forms of the verbs to be or to get followed by a passive participle as the subject complement—sometimes referred to as a passive verb.
English allows a number of additional passive constructions that are not possible in many other languages with analogous passive formations to the above. A sentence's indirect object may be promoted to the subject position—e.g. Tom was given a bag. Similarly, the complement of a preposition may be promoted, leaving a stranded preposition—e.g. Sue was operated on.
The English passive voice is used less often than the active voice, but frequency varies according to the writer's style and the given field of writing. Contemporary style guides discourage excessive use of the passive voice but generally consider it to be acceptable in certain situations, such as when the patient is the topic of the sentence, when the agent is unimportant and therefore omitted, or when the agent is placed near the end of a sentence as a means of emphasis.
Identifying the English passive The passive voice is a specific grammatical construction. The essential components, in English, are a form of the stative verb be (or sometimes get) and the past participle of the verb denoting the action. The agent (the doer of the action) may be specified using a prepositional phrase with the preposition by, but this is optional. It can be used in a number of different grammatical contexts; for instance, in declarative, interrogative, and imperative clauses: "Kennedy was assassinated in 1963." "Mistakes were made." "The window got broken." "Have you ever been kicked by an elephant?" "Don't get killed." "Being attacked by Geoffrey Howe was like being savaged by a dead sheep."
Misuse of the term Though the passive can be used for the purpose of concealing the agent, this is not a valid way of identifying the passive, and many other grammatical constructions can be used to accomplish this. Not every expression that serves to take focus away from the performer of an action is an instance of passive voice. For instance, "There were mistakes" and "Mistakes occurred" are both in the active voice. Occasionally, authors express recommendations about use of the passive unclearly or misapply the term "passive voice" to include sentences of this type. An example of this incorrect usage can be found in the following extract from an article from The New Yorker about Bernard Madoff (bolding and italics added; bold text indicates the verbs misidentified as passive voice):
The intransitive verbs would end and began are in fact ergative verbs in the active voice. Although the speaker may be using words in a manner that diverts responsibility from him, this is not being accomplished by use of passive voice.
Reasons for using the passive voice The passive voice can be used without referring to the agent of an action; it may therefore be used when the agent is unknown or unimportant, or the speaker does not wish to mention the agent. Three stores were robbed last night (the identity of the agent may be unknown). A new cancer drug has been discovered (the identity of the agent may be unimportant in the context). Mistakes have been made on this project (the speaker may not wish to identify the agent).
The last sentence illustrates a frequently criticized use of the passive, as the evasion of responsibility by failure to mention the agent (which may even be the speaker themselves).
Nonetheless, the passive voice can be complemented by an element that identifies the agent, usually via a by-phrase that is intended to emphasize the agent. For example: Don't you see? The patient was murdered by his own doctor!
In more technical terms, such uses can be expected in sentences where the agent is the focus (comment, rheme), while the patient (the undergoer of the action) is the topic or theme (see Topic–comment). There is a tendency for sentences to be formulated so as to place the focus at the end, which can motivate the choice of active or passive voice: My taxi hit an old lady (the taxi is the topic, and the lady is the focus). My mother was hit by a taxi (the mother is the topic, and the taxi is the focus).
Similarly, the passive may be used because the noun phrase denoting the agent is a long one (containing many modifiers) since it is convenient to place such phrases at the end of a clause: The breakthrough was achieved by Burlingame and Evans, two researchers in the university's genetic engineering lab.The American Heritage Book of English Usage (1996).
In some situations, the passive may be used so that the most dramatic word or the punchline appears at the end of the sentence.
Style advice
Advice against the passive voice Many language critics and language-usage manuals discourage use of the passive voice. This advice is not usually found in older guides, emerging only in the first half of the twentieth century. In 1916, the British writer Arthur Quiller-Couch criticized this grammatical voice:
Two years later, in the original 1918 edition of The Elements of Style, Cornell University Professor of English William Strunk, Jr. warned against excessive use of the passive voice:
In 1926, in A Dictionary of Modern English Usage, Henry Watson Fowler recommended against transforming active voice forms into passive voice forms, because doing so "......sometimes leads to bad grammar, false idiom, or clumsiness."
In 1946, in the essay "Politics and the English Language", George Orwell recommended the active voice as an elementary principle of composition: "Never use the passive where you can use the active."
The Columbia Guide to Standard American English states that:
Use of the passive is more prevalent in scientific writing, but publishers of some scientific publications, such as Nature, Science and the IEEE, explicitly encourage their authors to use active voice.
The principal criticism against the passive voice is its potential for evasion of responsibility. This is because a passive clause may be used to omit the agent even where it is important: We had hoped to report on this problem, but the data were inadvertently deleted from our files.
Krista Ratcliffe, a professor at Marquette University, notes the use of passives as an example of the role of grammar as "......a link between words and magical conjuring...: passive voice mystifies accountability by erasing who or what performs an action..."
Advice by style guides and grammarians on appropriate use of the passive voice Jan Freeman, a columnist for The Boston Globe, said that the passive voice does have its uses, and that "all good writers use the passive voice."
Passive writing is not necessarily slack and indirect. Many famously vigorous passages use the passive voice, as in these examples with the passive verbs italicized: Every valley shall be exalted, and every mountain and hill shall be made low; and the crooked shall be made straight, and the rough places plain. (King James Bible, .) Now is the winter of our discontent / Made glorious summer by this sun of York. (Shakespeare's Richard III, I.1, ll. 1–2.) We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness. (United States Declaration of Independence.) Never in the field of human conflict was so much owed by so many to so few. (Winston Churchill addressing the House of Commons, 20 August 1940.) Yesterday, December 7, 1941 - a date which will live in infamy - the United States of America was suddenly and deliberately attacked by naval and air forces of the Empire of Japan. (Franklin D. Roosevelt's Infamy Speech following the Attack on Pearl Harbor.) For of those to whom much is given, much is required. (John F. Kennedy's quotation of Luke 12:48 in his address to the Massachusetts legislature, 9 January 1961.)Address to Massachusetts legislature (Jan. 9, 1961)
While Strunk and White, in The Elements of Style, encourage use of the active voice, they also state that the passive is often useful and sometimes preferable, even necessary, the choice of active or passive depending, for instance, on the topic of the sentence.
Another advisor, Joseph M. Williams, who has written several books on style, states with greater clarity that the passive is often the better choice.For instance: According to Williams, the choice between active and passive depends on the answers to three questions: "Must the reader know who is responsible for the action?" "Would the active or passive verb help your readers move more smoothly from one sentence to the next? "Would the active or passive give readers a more consistent and appropriate point of view?" Bryan A. Garner, in Garner's Modern English Usage, stresses the advantages of the active voice, but gives the following examples of where the passive is preferred: "When the actor is unimportant." "When the actor is unknown." "When you want to hide the actor's identity." "When you need to put the punch word at the end of the sentence." "When the focus of the sentence is on the thing being acted on." "When the passive simply sounds better." Merriam–Webster's Dictionary of English Usage recommends the passive voice when identifying the object (receiver) of the action is more important than the subject (agent), and when the agent is unknown, unimportant, or not worth mentioning: The child was struck by the car. The store was robbed last night. Plows should not be kept in the garage. Kennedy was elected president. The linguist Geoffrey Pullum writes that "The passive is not an undesirable feature limited to bad writing, it's a useful construction often needed for clear expression, and every good writer uses it."
Despite criticism that the passive can be used to hide responsibility by omitting the agent, the passive can also be used to emphasize the agent. Writers have preferred placing the agent at the end of a clause or sentence to give it greater emphasis, as in the examples given in the previous section: Don't you see? The patient was murdered by his own doctor! The breakthrough was achieved by Burlingame and Evans, two researchers in the university's genetic engineering lab.
Actual use of the passive voice
Agentless passives were once common in scientific writing, where the agent may be irrelevant, although at least one publisher considers this a "fading practice": The mixture was heated to 300 °C.
The passive voice is used more frequently in scientific writing than in other prose, where it is relatively rare.
A statistical study of a variety of periodicals found a maximum incidence of 13 percent passive constructions. Despite Orwell's advice to avoid the passive, his Politics and the English Language employs passive voice for about 20 percent of its constructions.
The Longman Grammar of Spoken and Written English gives the following rough frequencies per million words: