Question Detail

Switch on the light.

Let the light be switch on.
Let the light should be switched on.
Let the light will be switched on.
Let the light be switched on.
Let the light switched on.

Answer: Option D

1. Rahul made her laugh.

She had made to laugh by Rahul.
She was made for laugh by Rahul.
She was made to laugh by Rahul.
She was made laugh by Rahul.

Answer: Option C

Explanation:

Note : Please note "made to laugh"

2. Thief killed him.

He was kill by the thief.
He killed by the thief.
He was killed by the thief.
He was killed.

Answer: Option C

3. I must help him.

He must helped by me.
I must held him.
He must get help from me.
He must be helped by me.

Answer: Option D

Explanation:

If we have "Subject + Modal Auxiliary verb + first verb + object"
then we change it to

Passive subject + Modal Auxiliary verb + be + third form + by + passive object.

Modal Auxiliary verb are : can, could, shall, will, may, might, should, would, must, ought to etc.