Exercise 3: Choose the correct option.

1. David came in when the children were writing a test. 2. Mike telephoned me when I was taking a shower. 3. Mike spoke to me when his little sister was taking his book out of his schoolbag. 4. We met them when we were standing at the bus stop. 5. I slept when his mother came back. 6. On Monday while he was cooking lunch the postman brought him a letter from his friend. 7. When the teacher came into the classroom, the children were sitting at their desks.