1. The exhibition was opened by the C.M.
2. America was discovered by Columbus.
3. The Ramayana was written by Valmiki.
4. The truth was told to her by them. (OR) She was told the truth by them.
5. He was praised by everyone.
6. A snake was killed by him.
7. The house was painted by them.
8. A song was sung by her.
9. The old house was pulled down by them.
10. A letter was written by me.
11. A dozen apples were brought by my father.
12. The letter was posted by him.
13. The bell was rung by the peon.
14. He was beaten by the teacher.
15. A heavy box was lifted by him.