6. She got up early yesterday morning _________ _______ (为了) she wouldn’t be late for school.

5. What language ________ _______ _________ (必须讲) in your English class ?

4. Fruit trees ________ ________ _________ (不能种) on the sides of the road .

3. The tree ______ ________ ________ (可以放) in the hole now.

2. Great Green Wall __________ ________ _______ (一定要修建) all over the world.

1. All the work _________ _________ _________ (应该做) as soon as possible .

5.　　 The homework must ___ carefully every day.

A.　 do　 B. done　 C. be done　 D. doing

4.　　 Now the tree must ______________ (tie) to the stick.

3.　　 Young trees must ______________ (look) after well.

2.　　 Many trees should _____________ (plant) on the mountains .