请老师判断主动句改的被动句，是否正确？如果错误，请指出并说明缘由。

1. They waste a lot of time discussing unimportant things.

被动句: A lot of time is wasted (in) discussing unimportant things. （正）

2.The police are sure to ask you that question.

被动句：

2a. You are sure to be asked that question. （正）

2b. That question is sure to be asked of you. （正；把to 改为of）

3. The instructor put him off driving altogether.

被动句：He was put off diving altogether by the instructor. （正）

4. It must have disappointed him terribly that people told him they didn’t want him.

被动句：He must have been disappointed by that people told him they didn’t want him. （误）

介词by 不能接that 从句。改为：

by the fact that people told him they didn’t want him.