They have to repair the engine of the car.
--> The engine of the car has to be repaired.
The boy broke the window and took away some pictures.
--> The window was broken and some pictures were taken away by the boy.
. A man I know told me about it.
--> It was told to me by a man I know
No one believes his story.
--> His story is not believed.
Do they teach English here?
--> Is English taught here ?
Will you invite her to your wedding party?
--> Will she be invited to your wedding party ?
Did the teacher give some exercises? Were some exercises given by the teacher?
Have they changed the window of the laboratory?
Has the window of the laboratory been changed?
Is she making big cakes for the party?
Are big cakes being made for the party?
Why didn't they help him?
Why wasn't he helped?
You mustn't use this machine after 5:30 p.m.
This machine mustn't be used after 5:30 p.m.
Toàn in sai chính tả thôi :)