1. He often came to see her last year.
2. I had read the book, before I gave it to my friend.
3. What were they doing yesterday at 7 o'clock?
4. He had been waiting for her for 5 years by the time she came.
5. We had much work to do yesterday.
6. They were at home by 6 o'clock yesterday.
7. I had written two letters to my friend by 6 yesterday.
8. She sent the letter after I had written it.
9. He was sleeping the whole long day yesterday.
10. We had been doing the work for many hours, before she came.