How do I change an imperative sentence into the passive?

Use the pattern “Let + object + be + past participle”. So “Do the work” becomes “Let the work be done”, and the negative “Do not shut the door” becomes “Let not the door be shut”. When the sentence is a polite request rather than a command, use “You are requested to …” instead.

Which tenses cannot be made passive?

The three perfect continuous tenses and the future continuous have no passive form. So “He has been reading the book” simply stays active. If a change you make produces something like “has been being read”, you have gone wrong — that form does not exist in ordinary English.

When should the "by" phrase be left out?

Whenever the doer adds nothing. Drop it when the doer is unknown (“My bicycle was stolen”), when it is everybody (“Rice is grown in Bangladesh”), or when it is obvious from context. In exam answers, keep the “by” phrase unless the active sentence used a vague subject such as someone or people .

What happens when the active sentence has two objects?

Either object can become the subject, so both passives are correct. “He gave me a pen” yields “I was given a pen by him” and “A pen was given to me by him”. Note that when the thing becomes the subject, the person needs to before it. Boards accept either version unless one is specified.

English · Grammar · SSC & HSC

Voice Change — Active to Passive Rules & Exercise

Active to passive and back, for every tense and every sentence type, with the cases that have no passive.

Voice shows whether the subject performs the action (active) or receives it (passive). To make a sentence passive, move the object to subject position, put the verb into "be + past participle" keeping the original tense, and move the original subject into a "by" phrase — dropping it when it is unknown or unimportant. Only transitive verbs have a passive form.

Where it is set: SSC & HSC English 2nd Paper — Grammar

The three steps of an active-to-passive change

Turning an active sentence into a passive one always involves the same three moves, in the same order. Do them mechanically and the sentence comes out right.

First, the object of the active sentence becomes the subject of the passive. Second, the verb becomes be plus the past participle, with be carried into the tense the active verb was in. Third, the original subject moves to the end after by — and is dropped whenever it is obvious, unknown or unimportant.

✓ Active: He writes a letter. → Passive: A letter is written by him.
✓ Active: Someone stole my bicycle. → Passive: My bicycle was stolen. — the doer is unknown, so the by phrase is dropped

The passive form of every tense

The verb form in each tense

Tense	Active	Passive
Present indefinite	He writes it.	It is written by him.
Present continuous	He is writing it.	It is being written by him.
Present perfect	He has written it.	It has been written by him.
Past indefinite	He wrote it.	It was written by him.
Past continuous	He was writing it.	It was being written by him.
Past perfect	He had written it.	It had been written by him.
Future indefinite	He will write it.	It will be written by him.
Future perfect	He will have written it.	It will have been written by him.
Modal	He can write it.	It can be written by him.

✓ They are building a bridge. → A bridge is being built. — continuous tenses insert being
✗ The work has completed. ✓ The work has been completed. — the perfect passive needs been

The tenses that have no passive

Not every tense can be made passive. The perfect continuous tenses and the future continuous have no passive form in ordinary English, so a board question will never ask for one — and if your answer produces one, you have made an error earlier in the sentence.

No passive: present perfect continuous, past perfect continuous, future perfect continuous, future continuous.
Only transitive verbs — verbs that take an object — can be made passive. He sleeps has no object, so it has no passive.
Some transitive verbs resist the passive by meaning: have, lack, resemble, suit, become, cost, hold (contain).

✓ He has been reading the book. — no passive form exists for this tense
✓ The shirt suits you. — suit has no natural passive

Imperative, interrogative and two-object sentences

Sentences that are not plain statements follow their own passive patterns. These carry a large share of the marks because they cannot be produced by applying the three basic steps alone.

Type	Active	Passive
Command	Do the work.	Let the work be done.
Negative command	Do not shut the door.	Let not the door be shut.
Request / advice	Please help me.	You are requested to help me.
Yes-no question	Did he write it?	Was it written by him?
WH question	Who broke the glass?	By whom was the glass broken?
WH question (object)	What did he say?	What was said by him?
Two objects	He gave me a pen.	I was given a pen. / A pen was given to me.

✓ Open the window. → Let the window be opened.
✓ Who wrote this letter? → By whom was this letter written? — who becomes by whom

Passive to active, and when the passive is the better choice

Reversing the change is simply the three steps run backwards: the by phrase becomes the subject, the passive verb returns to its active form in the same tense, and the old subject becomes the object. If there is no by phrase, supply a general subject such as someone, people or they.

Beyond the exam, the passive is not a worse form of the active — it is the right choice when the doer is unknown, unimportant, or deliberately not named, and when the thing acted upon is what the sentence is really about.

The road was repaired last week — nobody cares which crew did it.
Rice is grown in Bangladesh — the growers are everyone, so naming them adds nothing.
A mistake was made — the doer is being left unnamed on purpose.
Water is composed of hydrogen and oxygen — scientific writing keeps the focus on the thing described.

✓ Passive: The letter was posted yesterday. → Active: Someone posted the letter yesterday.
✓ Passive: English is spoken all over the world. → Active: People speak English all over the world.