Question

  Scientists think that there 1 life on the earth for hundreds of millions of years. However,we have not found life on any other planets 2 .

   The earth is a planet and it 3 around the sun. Seven other planets also go around the sun. 4 of them has an environment like that of the earth,5 scientists do not think they will find life on them. The sun and 6 planets are called the solar system,and our solar system is a small part of a much larger group of stars and planets,called the Galaxy or the Milky Way. There are millions of stars in the Galaxy,and our sun is only one of them.

   Scientists have also 7 many other galaxies in the universe. They are very far away and their light has to travel for many years to reach us. So how large is the universe? It is 8 to imagine.

   Scientists have sent spaceships to the planet Mars to take photos. They have even sent spaceships to travel outside the solar system. However,no spaceship has travelled 9 to reach other stars in our Galaxy.

   Scientists have always asked the questions： 10 so many stars in the universe,are we alone,or is there life out there in space? Have there been visitors to the earth from other planets? Why has no one communicated with us? We do not know the answers. . . yet.

1. A. will be   B. has been   C. was   D. has

2. A. yet   B. already   C. just   D. too

3. A. went   B. goes   C. going   D. to go

4. A. No one   B. None   C. Neither   D. Either

5. A. for   B. and   C. but   D. so

6. A. it   B. its   C. her   D. his

7. A. made   B. sent   C. invented   D. discovered

8. A. impossible   B. possible   C. easy   D. excited

9. A. old enough   B. large enough   C. fast enough   D. far enough

10. A. of   B. with   C. and   D. by

Answer 1

1〜5. BABBD 6〜10. BDADB