15. Children should be taught to _________ others.

答案:care for　 care for 意为“关怀，照顾”。

14. All human beings are much more _________ than animals.

答案:intelligent

13. You will _________ your health if you work so hard.

答案:endanger

12. The problem is so difficult that I can’t work it out. (改为简单句)

The problem is _________ difficult _________ work out.

答案:too to，

11. We planted many trees in our school yard. (改为被动语态)

Many trees _________ _________ in our school yard.

答案:were planted

10. I am not against building a new park in our town. (变为同义句)

I _________ _________ build a new park in our town.

答案:agree to

9. You should remember to take your own bags when you are shopping. (改为同义句)

_________ _________ to take your own bags when _________.

答案:Don’t forget，shopping

8. The animals in the cage are given food once a day. (对划线部分提问)

_________ _________ are the animals in the cage given food?

答案:How often　 how often 表示频率，意为“多久一次”。

6. A:I think we should stop using paper napkins.

　 B: _________ _________. It’s really a waste of money.

答案:I agree

7. Many animals are _________ _________.

　 We should do something to protect them.

答案:becoming endangered

5. We _________ paper to be recycled to save more trees.

A. suggest　　　　　 　B. expect 　　　　　C. agree　　 　　　D. hope

答案:B　 expect 意为“预料，期望”，后接复合宾语，其余选项无此用法。