1 . Have you ever noticed the Mu Us Desert (毛乌素沙漠) in the northwest when you read a map of China? If you haven’t, then you probably never will. That’s _______ the desert is disappearing.

You might wonder: Why is this happening? Who is the “killer”? Well, it is the _______ of years of efforts in tree planting. In China, the Mu Us used to be one of the largest deserts in size. Sandstorms were common in northern Shanxi. Lots of people had to leave their homes. The fight against desertification (沙漠化) began in the1970s. A team planned to plant trees in the desert. It once took them a whole afternoon to plant trees under a burning sun. That night, however, a strong wind blew away all the young trees. Crying was _______. The next day, the team replanted all the trees.

In Yulin, there are many other fighters. One of them is Guo Chengwang. He started to plant trees in his village when encouraged by the government in 1985. Guo is now in his nineties. His children, grandchildren and great-grandchildren have _______ the job. The family has turned 30 km² of desert into woods.

These trees have made a big difference. In Yulin, the number of sandy days has _______ from 100 in 2000 to 10 now. With the joined and continuing efforts, the Mu Us Desert will be gone. Our motherland will become greener and lovelier.

1.

A．why

B．how

C．because

D．when

2.

A．trouble

B．result

C．importance

D．reason

3.

A．necessary

B．serious

C．useless

D．harmless

4.

A．received

B．forgotten

C．changed

D．continued

5.

A．dropped

B．stayed

C．risen

D．disappeared

2 . Fiery Visitors from Outer Space

1. On the next clear summer night, look up into the sky. If you are lucky, you may see a “shooting star”. They look just like stars falling down from the sky.

2. But shooting stars are not stars at all. The real name for a shooting star is “meteor”. There are millions of meteors out in space. They are pieces of rock and metal. When they are in space, meteors do not glow. In fact, we can’t see them at all. But when a meteor comes close to the earth, it starts to fall toward the earth. As it passes through the air, it gets very hot. It starts to glow, and finally it begins to burn. We see the burning meteor as a shooting star.

3. Sometimes meteors travel by themselves in space. But many meteors travel in groups called swarms. The swarms have orbits like planets have. They pass close to the earth every year. A famous swarm is the Perseid swarm. It passes close to the earth in summer, usually in August. Each year a few meteors from the Perseid swarm fall to the earth, so August is a good month to watch for shooting stars.

4. Most meteors are small, so they burn up before they crash into the earth and are buried in the ground. Once a meteor reaches the earth, we call it a meteorite. The biggest meteorite, which weighs seventy tons, landed in Africa.

Question 19
1. Circle the main idea of paragraph 3.

A．Sometimes meteors travel by themselves in space.

B．Sometimes meteors travel in swarms.

C．A famous swarm is the Perseid swarm.

D．August is a good month to watch for shooting stars.

Question 20-23
Match the word on the left with the phrase on the right that fits best by writing letters.
2. ______ meteor
3. ______ swarm
4. ______ Perseid
5. ______ meteorite
a. a famous swarm of meteors
b. a meteor that has reached the earth
c. the real name for a shooting star
d. a group of meteors
Question 24-25
Answer questions in complete sentences and in your own words.
6. Why is August a good month to watch shooting stars?
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7. There is an old saying that if you make a wish when you see a shooting star, your wish will come true. So when you see a shooting star, what wish will you make? Why?
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