1. students have participated in a community project.

2. students who knew the answer to the advanced question was very small.

3. goats are eating the grass

4. students have already taken the test.

5. students absent from the English class.

6. gifts he received on his birthday made his friends surprised.

7. car owners in big cities has risen dramatically over the past years.

8. donated books will be sent to poor children tomorrow.

9. teachers have attended our school events.

10. dresses in this shop were bought by my sister.