Scientists are trying to make the deserts into good land again. They want to bring water to the deserts, so
people can live and grow food. They are learning a lot about the deserts. But more and more of the earth is
becoming desert all the time. Scientists may not be able to change the desert in time.
      Why is more and more land becoming desert? Scientists think that people make deserts. People are doing
bad things to the earth.
      Some places on the earth don't get much rain. But they still don't become deserts. This is because some
green plants are growing there. Small green plants and grass are very important to dry places. Plants don't let the
hot sun make the earth even drier. Plants don't let the wind blow the dirt away. When a little bit of rain falls, the
plants hold the water. Without plants, the land can become a desert much more easily.

1. Deserts _________.

A. get very little rain
B. never have any plants or animals in them
C. can all be turned into good land in the future
D. both A and C

2. Small green plants are very important to day places because ________.

A. they don't let the sun make the earth even drier
B. they don't let the wind blow the earth away
C. they hold the water
D. A, B and C

3. Land is becoming desert little by little because ________.

A. plants can't grow there
B. there's not enough rain
C. people are doing bad things to the earth.
D. scientists know little about desert

4. Which is the main idea of the first paragraph?

A. Scientists know how to change land into good land.
B. Land is becoming desert faster than scientists can change it back into good land.
C. If scientists can bring water to the desert, people can live there.
D. More and more places are becoming deserts all the time.

5. After reading this, we learn that ________.

A. plant can keep dry land from becoming desert.
B. it is good to get rid of (清除) the grass in the desert
C. all places without much rain will become deserts
D. it is better to grow crops on dry land than to grow grass

    Scientists (科学家) are trying to make the deserts (沙漠) into good land again. They want to bring water
to the deserts, so people can live and grow food. They are learning a lot about the deserts. But more and more
of the earth is becoming desert all the time. Scientists may not be able to change the desert in time.
    Why is more and more land becoming desert? Scientists think that people make deserts. People are doing
bad things to the earth.
    Some places on the earth don't get very much rain. But they still don't become deserts. This is because
some green plants are growing there. Small green plants and grass are very important to dry (干的) places.
Plants don't let the hot sun make the earth even drier. Plants don't let the wind blow (吹) the dirt (土) away.
When a little rain falls, the plants hold the water. Without plants, the land can become a desert much more
easily.

1. Deserts ______.

A. get very little rain
B. never have any plants or animals in them
C. can all be turned into good land soon
D. both A and C

2. Small green plants are very important to dry places because ______.

A. they don't let the sun make the earth even drier
B. they hold water
C. they don't let the wind blow the earth away
D. all of the above

3. Land is becoming desert little by little (渐渐地) because ______.

A. Plants can't grow there
B. There is not enough rain
C. People haven't done what scientists wish them to do
D. Scientists know little about the deserts

4. Which is the main idea of the first paragraph (段, 节)?

A. Scientists know how to change desert into good land.
B. Land is becoming desert faster than scientists can change it back into good land.
C. If scientists can bring water to desert, people can live and grow food there.
D. More and more places are becoming deserts all the time.

5. After reading this, we learn that ______.

A. plants can keep (阻止) dry land from becoming desert
B. it is good to get rid of (去除) the grass in the deserts
C. all places without much rain will become deserts
D. it is better to grow crops (农作物) on dry land than to grow grass

     Scientists(科学家) are trying to make the deserts (沙漠) into good land again . They want to bring
water to the deserts , so people can live and grow food . They are learning a lot about the deserts . But
more and more of the earth is becoming desert all the time . Scientists may not be able to change the
deserts . Scientists think that people make deserts . People are doing bad things to the earth .
    Some places on the earth don’t get very much rain . But they still don’t become desert . This is because some green plants are growing there . Small green plants and grass are very helpful to dry places . Plants
don’t let the hot sun make the earth even drier . Plants don’t let the wind blow the earth away . When a
little bit of rain falls , the plants hold the water . Without plants , the land can become a desert much more
easily .

1. Why can the land become a desert ?
A. Some places don’t get very much rain
B. Plants don’t let the hot sun make the earth even drier .
C. People don’t keep the earth well
D. Scientists haven’t learnt enough about the deserts .
2. Scientists ______ to make the deserts into good land again .
A. carry water
B. grow food
C. do nothing
D. study a lot
3. Which is not true ?
A. The land never stops becoming deserts .
B. Scientists ask the people to live in the deserts and grow food there .
C. People do bad things to the earth .
D. scientists may not be able to change the deserts .
4. Why are green plants and grass helpful ?
A. They can hold the water .
B. They can stop the wind from blowing the earth away .
C. They can keep the earth wet .
D. All the above .
5. Which is the best title (题目) for the passage ?
A. The Desert Problem
B. People Make Deserts
C. Green Plants and Grass
D. The Desert , the Tree and the Water

     Scientists are trying to make the deserts into good land again. They want to bring water to the deserts,
so people can live and grow food. They are learning a lot. about the deserts. But more and more of the earth
is becoming desert all the time. Scientists may not be able to change the desert in time.
     Why is more and more land becoming desert? Scientists think that people make deserts. People are doing
bad things to the earth.
     Some places on the earth don't get very much rain. But they still don't become deserts. This is because
some green plants are growing there. Small green plants and grass are very important to dry places. Plants
don't let the hot sun make the earth even drier. Plants don't let the wind blow the dirt away. When a little bit
of rain falls, the plants hold the water. Without plants, the land can become a desert much more easily.

(     )1. Scientists are trying to change the deserts into good land.
(     )2. Land is becoming desert little by little.               
(     )3. Scientists can change desert back into good land easily.  
(     )4. Small green plants need a lot of water.                   
(     )5. Plants can keep dry land from becoming desert.            

     Scientists are trying to make the deserts(沙漠)into a good land again. They want to bring water to the
deserts, so people can live and grow food. They are learning a lot about the deserts.  But more and more
of the earth is becoming deserts all the time. Scientists may not be able to change the deserts in time.
Scientists think that people make deserts. People are doing bad things to the earth.
     Some places on the earth don't get very much rain. But they still don't become deserts. This is because
some green plants are growing there. Small green plants and grass are very helpful to dry places. Plants
don't let the hot sun make the earth even drier. Plants don't let the wind blow the earth away. When a little
rain falls, the plants hold the water. Without plants, the land can become a desert much more easily.

1. What may cause the land become a desert, according to(根据) the writer?

A. Some places don't get very much rain.              
B. Plants don't let the hot sun make the earth even drier.              
C. People don't keep the earth well.              
D. Scientists haven't learnt enough about the deserts.

2. Scientists            to make the deserts into a good land again.

A. carry water    
B. grow food    
C. do nothing    
D. study a lot

3. Which of the following is NOT true?

A. The land never stops becoming deserts.              
B. Scientists ask people to live in the deserts and grow food there.              
C. People do bad things to the earth.              
D. Scientists may not be able to change the deserts.

4. Why are green plants and grass helpful?

A. They can hold the water.        
B. They can stop the wind from blowing the earth away.        
C. They can keep the earth wet.        
D. All the above.

5. Which of the following is the best title(标题) for the passage?

A. The Desert Problem.        
B. People Make Deserts.        
C. Green Plants and Grass.        
D. The Desert, the Tree and the Water.