Question

had he knocked at the door?
change into passive voice.
please give the format too​

Answer 1

Had the door been knocked by him?

Format with example is also there

Hope it helps...gm.....have a great day ahead

Answer 2

Answer:

Question:

Had he knocked the door?

Answer:

Had the door been knocked by him?

Format:

Let's do the interrogative sentence in simple sentence

>>> Had he knocked the door?

>>> He had knocked the door.

Now, let's do the passive voice of the simple sentence

>>> He had knocked the door.

>>> The door had been knocked by him.

Now, let's turn it into interrogative,

>>>The door had been knocked by him.

>>> Had the door been knocked by him?