用所给词的适当形式填空。

1. — How many teachers are there in your school? 

    — About 200. One third of them _____ (be) men teachers.

2. I'm sorry to keep you _____ (wait) for so long.

3. — What are you going to do, Tom?

    — I'm going to get my computer _____ (mend)

4. The Yangtze River is the third _____ (long) river in the world.

5. I'm looking forward to _____ (take) holiday in Hainan.