1. Could you tellus. what todo ( 做什么) to protect the environment?
2. When to have the meeting (什 么时候开会) hasn't been decided.
3.The difficulty was how to cross the river (怎样过河).
4. There are so many beautiful clothes and I don't know which one to choose (选 哪件).
5.i was wondering whether to follow his advice (是否听他的不见)。

1.Read 1a.
2. Memorize the useful expressions and key sentences which we learn in this topic. 
3. Finish Section D in your workbook.
4. Review what we have learned in this unit.