3. Some of the students 　　　　　　(sing) and some 　　　　　　(talk) when the teacher 　　　　　　(come) into the room.

2. Harry 　　　　　　(so) his lessons while his brothers 　　　　　(play) games.

1. My sister 　　　　　　(write) a letter when somebody 　　　　　　(come) in.

10.They 　　　　　　(watch) TV last night.

　 II.用所给动词的过去进行时或一般过去时填空.

9. Where 　　　you 　　　　　　(swim) at nine yesterday morning?

8. What 　　　he 　　　　　　(do) at four o’clock yesterday afternoon?

7. 　　　they 　　　　　　(have) a meeting when we got there.

6. Lily and Lucy 　　　　　　(not do) their homework yesterday morning.

5. 　　　it 　　　　　　(snow) hard when I stopped work.

4. My uncle 　　　　　　(not mend) his radio at nine this morning.