用所给的动词的适当形式填空（必要时可加助动词或情态动词）。

1．The students are having fun _________（ride）their bikes on the playground．

2．-- _________ I _________（use）your computer?

--Yes，you can．

3．Lisa _________（sweep）the floor at the moment．

4．It was very late．We stopped _________（work）and went home．

5．_________（not feed）the animals．Uncle Wang fed them five minutes ago．

6．_________（move）to Qingdao after I finish high school in 2012．

7．Arthur is trying _________（save）money for a new bicycle．

8．Do I have _________（clean）the living room?

9．_________ she（tour）the USA when she was fourteen?

10．_________（be）there any seals in the aquarium last weekend?