1 . 单句改错。判断下列句子是否存在时态使用问题，若有不当之处，找出后并加以改正
1. That was the first time I have been to such a big city. It’s so impressive.
2. Yesterday I didn’t drive him to the airport because my car was fixed at that time.
3. He kept the children out of the room because it was being cleaned.
4. I didn’t attend the meeting because I hadn’t told about it.
5. The room is being decorated when the man came in.
6. I hoped to send her a gift, but I didn’t manage it.
7. Up to now, he had not been very hard-working.
8. How many buildings had been destroyed when the hurricane ended?
9. By the time he got to the school, the first period has been finished.
10. As of last week, no trial date had been set.