科目: 來源: 題型:閱讀理解
Honeybees are disappearing for unknown reasons around the United States.Last winter, bees disappeared from 23 percent of American beekeeping businesses.Causes of the phenomenon, however, have remained a mystery.
Now, scientists from several universities and the United States Department of Agriculture say they have a possible explanation for the bee decline(數(shù)量下降).It is a little known virus called Israeli acute--paralysis virus (IAPV) .The virus kills bees.Researchers in Israel first described it in 2004 , but until now, bee experts hadn’t paid much attention to it.
When trying to find out why the bees were disappearing, a research team at Columbia University studied bee colonies ( 群體), some with and the others without decline.The research turned up large numbers of two types of fungi (真菌)once suspected of causing the bee decline.The research results, however, showed that the fungi were almost as common in colonies without a decline as they were in colonies with a decline.The researchers concluded that the two fungi probably weren’t the cause.
Studies of the presence of IAPV, however, showed more interesting information.In those studies, done by a team at Pennsylvania State University in University Park, the virus showed up in 83 percent of samples from colonies with symptoms (癥狀).Only five percent of samples from symptom less colonies had it.
Scientists still don’t know whether IAPIV can single--handedly cause the bee decline.They believe that even if the virus is making colonies sick , it could have a partner in crime.It’s possible, for instance, that insects or chemicals in the environment weaken bees, making them more likely to catch IAPV.
Scientists are still trying to figure out how IAPV came to the United States.The United States currently allows bee products to be imported from Canada, Australia, and New Zealand.If it turns out that this trade is spreading disease, the rules might eventually change.
1.According to the passage ,IAPV is a virus that ______.
A.hasn’t attracted much attention
B.well-known to doctors and scientist
C.was first found by Austrian researchers
D.is dangerous to animals and human beings
2.The underlined sentence in the fifth paragraph probably means______.
A.the virus could also cause other damages
B.there must be something that is the real cause
C.IAPV is not the only cause for the bee decline
D.the virus may be caused by the polluted environment
3.From the third and fourth paragraphs, we know researchers draw their conclusions by means of _______.
A.calculating B.comparing C.examining D.investigating
4.What still remains unknown to American scientists according to the passage?
A.How and why to kill IAPV.
B.How IAPV came to America.
C.Whether bee products should be imported.
D.How to change the rules of the bee products trade.
5.The best title for this passage would be _____.
A.Bee Disease B.How to Kill IAPV
C.A Virus—IAPV D.Two Types of Fungi
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根據(jù)所給漢語提示,完成下列句子,
1.His mother in the river.(禁止他游泳)
2.It he should apply for a patent for his invention.(這位發(fā)明家沒有想到……)
3.Let’s discuss the problem this Friday afternoon .(要是你方便的話)
4.Here was a chance for me that would catch snakes but not harm them.(通過發(fā)明某種仁慈的東西來表現(xiàn)一下自己)
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目前,越來越多的人擁有了自己的私人小汽車,你班同學(xué)就這一現(xiàn)象展開了一次討論,提出兩種不同的觀點(diǎn)和看法。假設(shè)你是李華,請(qǐng)按下表所列要點(diǎn)給報(bào)社寫一封信,客觀介紹這兩種觀點(diǎn),并說明你自己的看法。
贊同者的觀點(diǎn) | 反對(duì)者的觀點(diǎn) | 你的觀點(diǎn) |
方便、快捷、舒適帶動(dòng)其他行業(yè)發(fā)展,國家富強(qiáng) | 廢氣污染嚴(yán)重,影響交通導(dǎo)致更多事故,停車問題 | 贊成或反對(duì) |
注意:
1、詞數(shù):100左右。信的開頭已給出,不包括總詞數(shù)內(nèi)
2、可適當(dāng)增加細(xì)節(jié),以使行文連貫
3、參考詞匯:行業(yè)industry, 環(huán)境environment
Dear editors,
I’m writing to tell you about the discussion about whether it is good or not for families to own private cars.
Yours sincerely,
Li Hua
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Daniel’s father left home in 2001,and ever since.
A.has not heard of B.had not heard of
C.has not been heard of D.had not been heard of
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—Could you please put me through to 265?
一Hang on,please.I am doing that right now.
A.division B.crossing C.branch D.extension
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Freddy fell in love with Eliza, by her beauty and charm.
A.fascinated B.fascinating C.to be fascinated D.having fascinated
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Tom with his grandmother for eight years,but now he is living by himself.
A.lives B.lived C.has lived D.has been living
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Staring at the priceless diamond amazement, Mary dreamt of getting one.
A.with B.by C.a(chǎn)t D.in
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Carbon dioxide from burning fuels is the most common of the so-called greenhouse gases.
A.produced B.producing C.to be produced D.having been produced
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