ACTIVE AND PASSIVE SENTENCES

A. Relationship between active and passive:

1. The object of the active verb is the subject of the passive verb (“English” in the example sentences below). Therefore, verbs which cannot be followed by objects (intransitive verbs) cannot be used in passive voice.

These are some common intransitive verbs: appear, arrive, come, cry, die, go, happen, occur, rain, sleep, stay, walk. These verbs cannot be used in passive voice.

2. The passive verb always contains a form of the auxiliary verb be. The form of be in the passive verb phrase corresponds to the form of the main verb in the active verb phrase (see the underlined words in the example sentences below). That is, if the active main verb is simple present tense, then a simple present tense form of be is used in the passive verb phrase; if the active main verb is -ING, then the -ING form of be is used in the passive verb phrase; and so on.

3. The main verb in a passive predicate verb phrase is always the participle form of the verb.

4. Some examples of active and passive sentences:

ACTIVE: They speak English.
PASSIVE: English is spoken.

ACTIVE: They spoke English.
PASSIVE: English was spoken.

ACTIVE: They will speak English.
PASSIVE: English will be spoken.

ACTIVE: They are going to speak English.
PASSIVE: English is going to be spoken.

ACTIVE: They are speaking English.
PASSIVE: English is being spoken.

ACTIVE: They were speaking English.
PASSIVE: English was being spoken.

ACTIVE: They have spoken English.
PASSIVE: English has been spoken.

ACTIVE: They had spoken English.
PASSIVE: English had been spoken.

ACTIVE: They will have spoken English.
PASSIVE: English will have been spoken.

5. Perfect progressive verb forms are generally used in active voice only. That is, these are good English sentences:

ACTIVE: They have been speaking English.
ACTIVE: They had been speaking English.
ACTIVE: They will have been speaking English.

But sentences like these are rarely used:

PASSIVE: English has been being spoken.
PASSIVE: English had been being spoken.
PASSIVE: English will have been being spoken.

B. Most passive sentences do not contain an agent; all active sentences contain an agent.

1. An agent is the subject of the active verb. In the example sentences above, the agent is “they” in all the active sentences; the passive sentences do not contain an agent.

2. When a passive sentence contains an agent, it is in a prepositional phrase following the verb. For example:

English is spoken by them.

In the following sentences, the noun “teachers” is the agent in both sentences. “Teachers” is also the subject of the active verb, but “exams” is the subject of the passive verb.

ACTIVE: Teachers prepare exams.

PASSIVE: Exams are prepared by teachers.

C. You should not use passive voice unless you have a good reason.

Here are some good reasons for using passive voice:

1. Passive voice is often used when the agent (the doer of an action; the subject of an active verb) is obvious, unknown, or unnecessary:

Oranges are grown in California.
Toyotas are made in Japan.
Her purse was stolen.

2. Passive voice is often used when the agent is known, but the speaker/writer doesn’t want to mention it:

She was given bad advice.
A mistake has been made.

3. Passive voice is often used when the agent is very general such as people or somebody.

English is spoken here.
The door should be locked.

4. Passive voice is often used when the speaker/writer wants to emphasize a result:

Several thousand people were killed by the earthquake.

5. Passive voice is often used when the speaker/writer wants to keep the same subject for two or more verbs but this would not be possible if both verbs were the same voice (active or passive).

For example, in a conversation about George, a speaker would probably use sentence a below rather than sentence b (both sentences are correct).

a. George had several interviews before he was hired by a software company.
b. George had several interviews before a software company hired him.

SUMBER:
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