Active and passive voice concerns the subject of the sentence. If subject is active with respect to verbal action it is called active voice otherwise when subject seems less important than the verb it is passive voice. Now look at the following examples.
He is observing
It was observed that the situation was quite bad.
Now you see in the first example (1) the subject (he) is actively participating in verbal action (observation) whereas in the second example (2) it seems that the observation is more important than observer and that is why there is just no hint of the observer in a sentence, hence it is passive voice. All the examples in the tenses section are the examples of active voice where subject seems important and active.
Read the following keys and you will know how to convert any sentence into passive voice.
While converting any sentence into passive voice following FOUR major changes are essential.
1. Convert subject into object.
2. Convert object into subject.
3. Use past participle form (for example: gone, worked, understood etc).
4. Use by before object.
Now see the following example with complete detail of the changes.
Active voice: He always creates problems.
Passive voice: Problems are always created by him.
Subject (he) is converted into object
(him) in passive voice.
Object (problems) is converted into subject in passive voice and placed at the start.
3rd person singular form (creates) is converted into past participle (created).
By is used before object (him).
Now similarly there are more examples you should read so that you may understand the changes better and try them in your practice.
Active voice: She taught us English.
Passive voice: We were taught English by her.
Active voice: They made a bad mistake.
Passive voice: A bad mistake was made by them.
In order to understand the use of auxiliary you first need to see the tense of the sentence you want to convert into passive voice.
If sentence is indefinite tense use auxiliaries of continuous tense while converting into passive voice, like;
is, am, are with present indefinite tense
was, were with past indefinite tense
will be, shall be with future indefinite tense
He reads an interesting novel. (present
An interesting novel is read by him. (auxiliary of present continuous is)
You troubled us. (past indefinite)
We were troubled by you. (auxiliary of past continuous was)
We shall give you surprise. (future indefinite)
You will be given surprise by us. (auxiliary of future continuous will be.)
If sentence is of continuous tense use auxiliaries of the same tense by adding “being” with it.
He is chasing you. (present continuous)
You are being chased by him.
She was knocking at the door. (past continuous)
The door was being knocked at by her.
Note: Future continuous tense cannot be converted into passive voice because you cannot use will be being or shall be being.
If sentence is in perfect tense use auxiliaries of the same tense by adding “been” with it.
He has learnt French in a month. (present
French has been learnt by him in a month.
They hadn’t attended the church
this Sunday. (past perfect)
The church hadn’t been attended by them this Sunday.
Brown will have bought a new car. (future
A new car will have been bought by Brown.
There are FOUR tenses that cannot be converted into passive voice as mentioned below.
perfect continuous tense
Past perfect continuous tense
Future perfect continuous tense
Future continuous tense