1 . 请先阅读下面短文,掌握其大意,然后用方框中所给词的适当形式填空,并将答案填写到答题卡的相应位置。每个词限用一次。

know     life     different     back     and     interesting     sign     real     find     they

The planet Mars is the closest and most similar planet to Earth. It is very    1    to scientists. For example, Mars has seasons with    2    weather, but other planets have the same temperatures all year round. Was there    3    on Mars?

To find out, scientists need    4    if Mars ever had water. In 2004. two robot explores (探测器), or 'rovers', called Spirit and Opportunity were sent to look for    5    of water. These rovers can drive over rocks    6    all kind of rough ground. They can also use cameras and send photos    7     to Earth. First, the two rovers found chemicals and patterns (图文) in the rocks that were probably made by water. Then, they moved to another area and    8    other rocks which may have been created by water. Now scientists think there was probably water on the planet long ago. Today       9    are still not sure if there was life on Mars. They    10    need more information to decide. The discoveries of the two rovers answered some old questions, but they also brought up many new ones.

2 . The universe is really mystical(神秘的). Scientists have done lots of study about it but there is still much they haven’t discovered. ___ think that people have lived on the earth for many many years. However, we haven’t found life on any other planets _____.

There _____ eight planets going around the sun. The earth is one of them. There are humans, animals, plants and many other kinds of _____ on the earth. There is water and air, too. And compared to the other planets, the earth is not too _____ or too cold. None of seven other planets has a(n) _____ like that of the earth.

The sun and its planets are_____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 billions of_____ in the Galaxy, and our sun is only one of them.

Scientists have also_____many other galaxies in the universe. Their light has to travel for many years to reach us. So how______ is the universe? It is impossible to imagine______.

Scientists have sent spaceships to the planet Mars to take______photos. They have______ sent spaceships to travel outside the solar system. However, no spaceship has travelled far enough to reach other stars in _____ Galaxy.

When we see stars twinkling(闪耀) in the sky at night, we may think a lot:with so many stars in the universe, is there life out there in space? If there is life on other planets, what life will be like there? What transports do they use to travel______? Why don’t they visit us? We do not know the answers...

1.

A．Workers

B．Doctors

C．Scientists

D．Managers

2.

A．yet

B．already

C．still

D．just

3.

A．is

B．are

C．was

D．were

4.

A．plant

B．life

C．animal

D．nature

5.

A．cool

B．warm

C．hot

D．wet

6.

A．lesson

B．house

C．expression

D．environment

7.

A．caused

B．carried

C．explained

D．called

8.

A．lights

B．rivers

C．stars

D．gods

9.

A．discovered

B．invented

C．produced

D．prevented

10.

A．large

B．far

C．wide

D．long

11.

A．introduce

B．overcome

C．appear

D．imagine

12.

A．fetch

B．take

C．carry

D．bring

13.

A．pretty

B．just

C．even

D．also

14.

A．her

B．our

C．its

D．his

15.

A．travel

B．serve

C．throw

D．beat

3 . Our sun is a star, and nine worlds (天体) move round it. Worlds like these are planets. But there are other stars, other suns, not only thousands of them, but millions of them. Do different stars have planets? We can see the planets round our own sun. but we haven’t been anymore. The stars are too far away from us. Stars give out light, but the planets don’t have any light of their own. So we can’t see them. They are too far, and too dark. Still, we can tell that some stars have planets. While a big planet goes round, it pulls its star to one side. And sometimes we can see this. Then we know that the star has a planet. For example, Barnard’s Star is a small red star. And it is the quickest star in the universe. But sometimes it moves slower, and then quicker again. We have known Bernard’s Star for many years, and now we are sure it has a planet.

1. A star is a large body in the universe. It _________.

A．moves round our sun	B．has light of its own
C．can also be called a sun	D．both B and C

2. Which of the following is not true?

A．The earth is one of the sun’s world’s

B．There are millions of suns in the universe

C．The worlds are very bright

D．some stars have planets

3. We can see the planets round our sun. But we can’t see ________.

A．nine worlds in the universe

B．the planets round other stars

C．the satellites round the earth

D．other stars

4. Barnard’s Star moves more quickly than ________.

A．most stars	B．any other star
C．its planet	D．the planets round the sun

5. How can people know that there is a planet round Barnard’s Star?

A．Sometimes they see that the planet pulls the star to one side and makes it move slower.

B．The planet is shining

C．The planet is next to our earth.

D．The planet is a red one.

4 . There is nothing more i    1     to life than the sun. W    2     the sun, all living things on the earth would die. The sun is a star. In the sky there are t    3     of stars like the sun. They are as large as the sun and as h    4     as the sun. At night you can see many stars, but in the day you can only see one star—the sun.

The sun is much n    5     to us than any other star. That is w    6     it looks the biggest and brightest of all the stars. The distance (距离) of the sun from the earth is as m    7     as 150,000,000 kilometers. Most stars are thousands of light-years a    8     from the earth.

Do you know what a light-year is? N    9     in the world travels faster than light. It travels 300,000 kilometers per second. And one light-year is the distance that light can travel in one y    10    .