10. Do you know how the greenhouse effect      (产生）？

9. We__________________________ (缺少) water, so we must save every drop of it.

8. We now       (跟……保持联系）each other by email.

7. Nobody can      (带走） these books from the reading room. You must read here.

6. The patient is getting better and better ________________ (一天天）

5. We must      (采取措施)control air pollution.

4. Some energy sources will never       ____  (用光).so we call them renewable sources.

3. Reading in the sun__________  ________ ____  (对...有害)your eyes.

2._________________ (令我吃惊的） he didn't arrive on time.

1.How do you want to__________________ (处理) the old computer?