用所给单词的适当形式填空。
1. Listen! The girl ______ (sing) in the room.
2. What time ______ your mother ______ (go) to work every day?
3. May I ______ (borrow) your eraser?
4. Tom usually ______ (come) to school at seven in the morning.
5. Jack ______ (swim) in the river now.
6. ______ (be) there any milk in the cup?
7. The students ______ (have) an English class yesterday.
8. Sue ______ (clean) the windows every day.