Question

Why would an animal kill itself? It seems a strange question, and yet it is one that has made some scientists curious for a long time. For there is a kind of animal called lemming（旅鼠）, that periodically killed themselves together, and no one knows just why!

The small creatures which live in the Scandinavian mountains, feed on a diet of roots and special insects and live in nests they dig underground. When their food supply is large, the lemmings live a normal and undisturbed life. 

However, when the lemmings’ food supply becomes too low to support the population, a singular migration（遷徙）begins. The lemmings leave their nests in groups. Great numbers of them begin to travel across the Scandinavian plains, a journey that may last weeks. The lemmings eat everything in their path, continuing their long march until they reach the sea. 

The reason for what follows remains unbelievable to naturalists. Upon reaching the coast, the lemmings do not stop but swim by the thousands into the sea. Most stay afloat only a short time before they tire, sink and drown. 

A common theory for this mass self-killing is that the lemmings do not realize that the ocean is such a huge body of water in their cross-country journey, the animals must cross many smaller bodies of water, such as rivers and small lakes. They may think that the sea is just another such swimmable path to go through. But no final answer has been found to the strange happening. 

1.The passage is mainly about______.

A. how lemmings find food

B. why animals kill themselves

C. the lemmings’ self-killing

D. the food supply in the Scandinavian mountains

2.A reason for the lemmings’ self-killing might be that they______.

A. go mad from a lack of food

B. hope to find fish for food

C. decide to reduce the population

D. think they can cross the sea

3.Why are scientists curious about the lemmings’ behavior?

A. Because they are the only animals that live in Scandinavia.

B. Because it is very unusual for animals to kill themselves.

C. Because of the amount of food they can eat on their march to the sea.

D. Because they can gather together in such huge numbers.

4.The underlined word “singular” means______.

A. unusual       B. single       C. wonderful      D. common

 

Answer 1

【答案】

 

1.C

2.D

3.B

4.A

【解析】

試題分析：文章大意：介紹奇異的旅鼠集體自殺現(xiàn)象及對其原因的推測。

1.主旨大意題第一段引出旅鼠定期集體自殺的話題，然后介紹他們的習(xí)性，接下來因?yàn)槭澄锕��?yīng)不足而進(jìn)行遷徙，到達(dá)海邊，然后集體渡海，體力不支死亡。最后一段是人們對于這種現(xiàn)象的推測。文章主要介紹的是旅鼠的自殺現(xiàn)象。選C

2.細(xì)節(jié)理解題：根據(jù)最后一段：旅鼠可能沒有意識到海洋那么廣闊，他們可能認(rèn)為大海不過是可以游過去的。選D

3.推理判斷題根據(jù)文章最后一句：But no final answer has been found to the strange happening.但是對于這種奇特現(xiàn)象至今還沒有最終的解答，導(dǎo)致科學(xué)家們對于旅鼠的異常行為非常好奇。選B。

4.詞義猜測題旅鼠的這次遷徙導(dǎo)致了不同于尋常動(dòng)物遷徙的結(jié)果，所以這是unusual: 不同尋常的；非同尋常的。single: 單一的；單身的；單程的；wonderful: 奇妙的；極好的；common: 共同的；一般的；普通的。選A

考點(diǎn)：考查科普類文章閱讀。