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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 sun make the earth even drier. Plants do not let the wind blow the dirt away. When a bit of rain falls,the plants hold the water. Without plants,the land can become desert more easily.

1.Deserts ________ .

A.never have any plants or animals in them

B.can all be turned into good land before long

C.a(chǎn)re becoming smaller and smaller

D.get very little rain

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 don’t let the wind blow the soil away

C.they hold water

D.All of the above.

3.Land is becoming desert little by little 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.After reading this passage, we learn that ________.

A.plants can keep dry land from becoming desert

B.it is good to get rid of the grass in the deserts

C.a(chǎn)ll places without much rain will become deserts

D.it is better to grow crops on dry land than to cut them

 

【答案】

1.D

2.D

3.C

4.A

【解析】

試題分析:

1.推理題:從第一句話:They want to bring water to the deserts, so people can live and grow food. 可知沙漠的水很少。選D

2.排除題;文章第三段提到ABC沒(méi)有提到D。

3.推理題:從文章第二段看出,科學(xué)家認(rèn)為是人導(dǎo)致沙漠的。可知C正確

4.推理題:從最后一句話:Without plants,the land can become desert more easily. 可知植物可以阻止土地變成沙漠。選A

考點(diǎn); 考查環(huán)保類短文

點(diǎn)評(píng):本文講述的是樹(shù)木對(duì)土壤的重要性。呼吁人們多種樹(shù),保護(hù)樹(shù)木,防止土地沙漠化。文章內(nèi)容比較簡(jiǎn)單,只需要讀懂文章的即可,以細(xì)節(jié)題為主。

 

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