1. She cooked yesterday.
2. She was cooking at three o'clock yesterday.
3. She was cooking from two till four yesterday.
4. I was reading at five o'clock.
5. I was reading when you came in.
6. What was he doing when I came?
7. What did he do the whole day yesterday?
8. Pete watered flowers in the garden yesterday.
9. Pete was watering flowers in the garden at five o'clock yesterday.
10. What was Pete doing when I came to see him?