Question

I saw him. (turn into passive voice

Answer 1

he was seen by me

hope it helps

Answer 2

When using the active voice, the subjects are the ones performing the action.

e.g:

God loves all men.Birds build nests.Dog eats bones. 

In these three sentences the subject does the action. Hence they are in the active voice.Passive voice=In the passive voice, the verb takes an object.

e.g:

All men are loved by God.Nests are built by birds.Bones are eaten by dog.

These sentences are in passive voice. The Passive voice is used in English