1. A. The mother had left the room before the child fell asleep.B. The mother left the room after the child had fallen asleep.2. A. I met Jack when I went to Seattle the last time.B. I met Jack at last when I went to Seattle.3. A. I had fun when I played badminton the second time.B. I began to have fun when I played badminton the first time.4. A. We take a hike whenever she visits.B. We take a hike almost each time she visits.5. A. We go to have lunch at Dick’s every time he comes.B. We often go to have lunch at Dick’s when he comes.6. A. Since I was young I have played tennis.B. I played tennis when I was a young girl.7. A. Most of the guests had arrived when he got to the party.B. Few guests were there when he arrived at the party.8. A. The students stopped talking when the teacher came in.B. The students stopped to talk when the teacher came in.9. A. I was doing my homework while she was cooking.B. I was cooking while she was doing homework.10. A. The train came in just before I arrived at the station.B. The train came in just after I arrived at the station.