用所给词的适当形式填空(5分)

1.Listen!  Kate __________ (sing) in the next room.

2.Look!  Two boys __________ ( play) basketball in the classroom. 

3.She __________ (swim) at the pool now. 

4.Tom __________ (write) a book these days. 

5.What’s your sister doing?  She __________ ( clean) her room.