选出适当的词填空。

1. A:I need some money. What _______ ( could; should) I do?

    B: You should get a part-time job.

2. A: I don't want to study at the library.

    B: You _______ ( shouldn't; could)  study at my  house.

3. A: This shirt is really ugly.

    B: Then you _______( could; shouldn't)  wear it  to  school.

4. A: I don't like writing letters.

    B: You _______ ( could; shouldn't) use the telephone.

5. A: I want to surprise my parents.

    B: You_______ ( shouldn't;could) buy them a CD.