用所给单词的适当形式完成句子。
1. The water in our city is _ __ (recycle) many times.
2. A new bridge is being ___ (build) in the river.
3. These boys are __ (pull) their boat out of the lake.
4. Many _ (roof) were blown away by the strong wind.
5. We can see a lot of _ _ (can) on the ground in the park.
6. The old school _ (pull) down and a new one is being built.
7. My sister joined a university film _ (social).
8. Some students (dance) while others were singing.
9. You should stop (worry) about it.
10. Our new school is the ____.
1. recycling 2. built 3. pulling 4. roofs 5. cans 6. was pulled 7. society 8. were dancing 9. worrying 10. most beautiful