Read the following sentences:
He is writing a letter. (Active)
A letter is being written by him. (Passive)
You will have noticed that the verb changes its form when the sentence is changed from the active voice to the passive voice. The passive form of the verb is constructed by putting appropriate auxiliary verbs before the past participle form of the active verb.
The active and passive forms of the verb write are given below:
When the active verb is in the simple present tense
Active verb: write/writes
Passive verb: is/am/are written
He writes a letter.
A letter is written by him.
When the active verb is in the present continuous tense
Active verb: is/am/are writing
Passive verb: is/am/are being written
He is writing a letter. (Active) A letter is being written by him. (Passive)
When the active verb is in the present perfect tense
Active verb: has/have written
Passive verb: has/have been written
He has written a letter. (Active) A letter has been written by him. (Passive)
When the active verb is in the simple past tense
Active verb: wrote
Passive verb: was/were written
He wrote a letter. (Active) A letter was written by him. (Passive)
When the active verb is in the past continuous tense
Active: was/were writing
Passive: was/were being written
He was writing a letter. (Active) A letter was being written by him. (Passive)
When the active verb is in the past perfect tense
Active verb: had written
Passive verb: had been written
He had written a letter.
A letter had been written by him.
When the active verb is in the simple future tense
Active verb: will/shall write
Passive verb: will/shall be written
He will write a letter. (Active) A letter will be written by him. (Passive)
When the active verb is in the future perfect tense
Active verb: will/shall have written
Passive verb: will/shall have been written
He will have written a letter.
A letter will have been written by him.
