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4、A classic series of experiments to determine the effects of overpopulation on communities of rats was conducted by a psychologist，John Calhoun．In each experiment，an equal number of male and female adult rats were placed in an enclosure（場(chǎng)地）．The rat populations were allowed to increase．Calhoun knew from experience approximately how many rats could live in the enclosures without experiencing stress due to overcrowding．He allowed the population to increase to approximately twice this number Then he fixed the population by removing the children that were not dependent on their mothers．At the end of the experiments，Calhoun was able to conclude that overcrowding causes a breakdown in the normal social relationships among rats，a kind of social disease．The rats in the experiments did not follow the same patterns of behavior as rats would in a community without overcrowding．

       The females in the rat population were the most seriously affected by the high population density（密度）．For example，mothers sometimes deserted their children，and，without their mothers’ care，the children died．The experiments showed that in overpopulated communities，mother rats do not behave normally．Their behavior may be considered diseased and pathological（病理學(xué)的）．

       The leading males in the rat population were the least affected by over population．Each of these strong males claimed an area of the enclosure as his own．Therefore，these individuals did not  experience the overcrowding in the same way as the other rats did．．However leading males did behave pathologically at times．Their antisocial（反社會(huì)）behavior consisted of attacks on weaker male，female，and immature rats．This unusual behavior showed that even though the leading males had enough living space，they too were affected by the general overcrowding．

       Non-leading males in the experimental rat communities also exhibited unusual social behavior．Some withdrew（縮回） completely ,avoiding contact with other rats．Other non-leading males were too active，chasing other rats and fighting each other．

       The behavior of the rat population has similarity in human behavior．People in densely（密） populated areas exhibit unusual behavior similar to that of the rats in Calhoun’s experiments．In large urban areas，such as New York City，London，and Cairo，there are deserted children．There are cruel，powerful individuals，both men and women．There are also people who withdraw and people who become too active．Is the major cause of these disorders（混亂）overpopulation?

       Calhoun’s experiments suggest that it might be．In any case，social scientists and city planners have been influenced by the results of this series of experiments．

1．Which of the following inferences（推斷）can NOT be made from the first paragraph?

       A．Overpopulation causes pathological behavior in rat populations．

       B．Calhoun had experimented with rats before．

       C．Calhoun’s experiment is still considered important today

       D．Stress does not occur in rat communities unless there is overcrowding．

2．The author implies that the behavior of the leading male rats is sometimes similar to that of

       A．people who would like to keep to themselves

       B．people who abandon their children

       C．too active people

       D．cruel，powerful people

3．The main point of this passage is that _______________．

       A．a(chǎn)lthough rats are affected by overcrowding，people are not

       B．overcrowding may be an important cause of social pathology

       C．the social behavior of rats is seriously affected by overcrowding

       D．Calhoun's experiments have influenced many people

3、       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

2、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）

1、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。

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

28、Not only I but also Brown and Kelly ___________ fond of rock music and computer games.

A．is                    B．a(chǎn)re                  C．a(chǎn)m                  D．be

27、After a knock at the door, the child heard his mother’s voice ____________ him.

A．calling           B．called           C．being called          D．to call

26、A small plane crashed into a hillside five miles east of the city, __________ all four people on board.

A．killed               B．killing              C．kills             D．to kill

25、______________ that he was in great danger, Eric walked deeper into the forest.

A．Not realized                                  B．Not to realize

C．Not realizing                                 D．Not to have realized

24、He asked us to write an article in_____________ of pollution caused by the nearby factories.

A．honor           B．search           C．respect         D．charge