1. 句型转换。

1. （1） We plant many trees every year. (改为被动语态)

   Many trees by us every year.

3. （2） About one fifth of the people in the world speak Chinese. (改为被动语态)

   Chinese by about one fifth of the people in the world.

5. （3） The work was finished by us three hours ago. (改为主动语态)

   We the work three hours ago.

7. （4） I am excited to visit Disneyland! (改为感叹句)

   I am to visit Disneyland!