1. She cooked yesterday.
2. She cooked at three o'clock yesterday.
3. She was cooking from two till four yesterday.
4. I didn't read at five o'clock.
5. I wasn't reading when you came in.
6. What was he doing when I came?
7. What was he doing the whole day yesterday?
8. Pete watered flowers in the garden yesterday.
9. Pete watered flowers in the garden at five o'clock yesterday.
10. What was Pete doing when I came to see him?