5. The meeting began with a _________________(讨论) about a survey .

4. Our Earth is becoming more and more __________ (拥挤的) and ___________ (被污染的).

3. Should we be able to ____________ (grow and improve) plants that can grow on Mars?

2. The ____________ (a power that keeps us from floating in the air) on Mars is a problem.

1. Food will be in the form of ___________ (small round pieces of medicine) on Mars.

We are always 　1　 ,‘Is there life on Mars?’We all know that it is difficult for people on Earth to live on Mars because we need water and oxygen to 　2　 , but there is little oxygen on Mars.

Living on Mars seems like living on a very high mountain. There is a very thin 　3　 . It might be 20 degrees above zero at noon and 60 degrees below zero 　4　 .

A lot of people think there may be plants on Mars. We know that Mars has carbon(碳).This is a kind of material 　5　 　in all plants and animals on Earth. Through a telescope, Mars looks red. In some places, it seems grey. At times the grey colour turns grey-green, then brown, and then grey again. The grey-green colour may be a kind of __6　 　life changing colour 　7　 the seasons. At first scientists thought the red planet was as 　8　 　as the moon with dust storms blowing over the large sandy deserts. But Mars seems not as __9　 　as we once believed it to be. According to an analysis on the recent Mars pictures, some scientists believe there is lots of 　10　 　on Mars and water is still in the form of ice. If there is water, there will be hope of finding life on Mars.

1. A. talking　 　　 B. wondering　 C. knowing　 　　 D. telling

2. A. drink　　 B. eat　　　　 C. survive　 　 D. breathe

3. A. air　　　 B. atmosphere 　　　 C. oxygen　 　　 D. gas

4. A. at night　 　　　　　　　　　　 B. in the daytime 　

C. in the morning　 　　　　　　　 D. in the afternoon

5. A. to find　　 　 B. finding　　 　 C. find　　　 　 D. found

6. A. animal　　 　 B. plant　　　 　 C. earth　　 　 D. people

7. A. for　　　 　　 B. by　　　　 　 C. along　　 D. with

8. A. lifeless　 　 B. hopeless　 　 C. harsh　　 D. alone

9. A. cold　　　 　　 B. hot　　　 　　　 C. dry　　　 　　 D. wet

10. A. water　　 　　 B. ice　　　 　　　 C. plants　　 　 D. life

20. He didn’t spend enough time on maths. _________, he failed the exam.

　 A.Although　 B. Even though　　 C. As a result　　 D.So

19. There is something wrong with my DVD player. I’ll have it ______.

　 A. fixed　　 B.to fix　　 C.fixes　　 D.fixing

18. In this match, who do you _____ to win ?

A. hope　　 B. expect　　 C. prefer　　 D. make