10. We should do something to stop them   (cut) the trees.

9. Suddenly,he saw his son   (fall) off his bike.

8. There   (be) a football match next week,isn’t there?

7. The boy tried his best   (open) the door,but failed.

6. How interesting it is   (row) a boat on the lake.

5.   (not pour) rubbish into the clean water,little boy.

4. I'm sorry I   (forget) to bring my homework here.

3. Now,the students   (plan) to have a picnic in the country tomorrow.

2. I   (pay) 50 yuan for my dress yesterday.

1. His mother   (leave) her key at home,so she couldn’t come into the house.