When an ant dies, other ants take it out of the nest, often within an hour after its death. This behavior interests scientists and they wonder how ants know for sure—and so soon—that another ant is dead.
One scientist recently came up with a way to explain this ant behaviour. Dong-Hwan Choe is a biologist, a scientist who studies animals and plants. He found that ants have a chemical on the outside of their bodies that signals to other ants, “I'm dead—take me away” when it is dead.
But there's a question to answer: As we know, if an ant is dead, it stops moving. But when an ant is sleeping or knocked unconscious, it is also not moving. However, other ants don't move the living ant out of the nest. How do they know this ant is not dead? Choe found that ants have another chemical on their bodies, which tells nearby ants something like, “Wait—I'm not dead yet” when it is not dead. Choe suspects that when an ant dies, the chemical that says, “Wait I'm not dead yet” quickly goes away. When other ants detect the “dead” chemical without the “not dead yet” chemical, they move away the body.
To test his theory , Choe and his team put different chemicals on ants. When the scientists used the “I'm dead” chemical, other ants quickly moved the treated ant away. When the scientists used the “Wait—I'm not dead yet” chemical, other ants left the treated ant alone. Choe believes this behavior shows that the “not dead yet” chemical overrides the “dead” chemical when picked up by other ants. And that when an ant dies, the “not dead yet” chemical fades away. Other nearby ants then detect the remaining “dead” chemical and remove the body from the nest.
Understanding this behavior can help scientists figure out how to stop ants from invading new places and causing problems.
小題1:What is the function of the first paragraph?
A.Leading the following paragraphs.
B.Showing the main idea of the passage.
C.Introducing the background of the passage.
D.Giving a summary of the passage.
小題2:Which of the following has the closest meaning to the underlined word “overrides” in the fourth paragraph?
A.is weaker thanB.is stronger thanC.is better thanD.is worse than
小題3: What can we learn from the passage?
A.Living ants can also be taken away when they are not moving.
B.When an ant dies, it can tell others using a certain chemical.
C.A living ant can pretend to be dead using a special chemical.
D.Ants often use chemicals to communicate with each other.
小題4:Which of the following descriptions about Dong-Hwan Choe is right?
A.Choe did this study in order to stop ants from invading new places.
B.Choe is a biologist who is only interested in animals, especially in ants.
C.Choe first came up with an idea to explain this ant behavior,and then did some tests to prove his theory.
D.Choe did the research on this ant behavior on his own

小題1:A
小題2:B
小題3:B
小題4:C

試題分析:
小題1:A 推理題。文章第一段介紹了這個有趣的現(xiàn)象,目的是為了引起下文。故A正確。
小題2:B 推理題。When the scientists used the “Wait—I'm not dead yet” chemical, other ants left the treated ant alone. Choe believes this behavior shows that the “not dead yet” chemical overrides the “dead” chemical when picked up by other ants.當科學家用“Wait—I'm not dead yet”的時候,其它螞蟻就不去搬動那個螞蟻說明這中chemical的訊息要強于“dead” chemical。故B正確。
小題3:B 細節(jié)題。根據(jù)第二段2,3行He found that ants have a chemical on the outside of their bodies that signals to other ants, “I'm dead—take me away” when it is dead.說明B正確。
小題4:C 推理題。根據(jù)第2段和第4段,在第2 段中他提出這個理論,在第四段中他做了實驗來證明自己的這個理論。故C正確。
點評: 文章介紹了一個實驗,螞蟻是如何識別同伴的死亡情況的。原來是運用化學物質(zhì)來判斷。本文要求考生能根據(jù)上下文的串聯(lián)來選擇合適的推斷,要準確定位。
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小題2:
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                              D
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B.they used to work and study without a moment’s rest.
C.they had received more schooling than other people
D.they know how to study and worked hard
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科目:高中英語 來源:不詳 題型:閱讀理解

Tourism probably started in Roman times. Rich Romans visited friends and family who were working in another part of the Roman Empire. But when the empire broke down,this kind of tourism stopped.
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In the 18th century, tourism began to change. For example, people in the UK started to visit some towns, such as Bath to” take the waters”. They believed that the water there was good for their health. So large and expensive hotels were built in these towns.
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  The 20th century saw cars become more and more popular among ordinary people. Planes were made larger, so ticket prices dropped and more people used them.
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A.a(chǎn)ll came from Roman
B.were very young and strong
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A.in 1949B.in Roman times
C.in the early 17th centuryD.in the 19th century
小題4:The underlined phrase “take off” means ________.
A.a(chǎn) plane rising into the air
B.develop very fast
C.remove hats and clothes
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