题目内容

Section B
Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice.
Disease can be one of the most powerful factors in checking population growth. In crowded conditions where many individuals of a species are living close together, the spread of pathogens (病原体) from one individual to another, occurs readily. History shows many instances where human populations, crowded together in cities, have been almost wiped out by the rapid spread of disease. Modern orchard and forestry practice recognizes this fact and the close planting of trees of the same species is avoided. Mixed forests and orchards are the recognized procedure these days.
Apart from regulating population numbers in other species, disease has probably been the greatest factor in controlling the growth of the human population.
In the mid 14th century, the Black Death wiped out 25 million people in Europe alone, while as recently as 1918 over 21 million people died in a single year as a result of the influenza epidemic. The relative stability of the human population has been upset by advances in medical science. No longer does disease regulate human population growth in many parts of the world. Medical cures have prolonged life and upset the age structure of many populations, increasing the proportion of individuals in the reproductive age group.
The decrease in distribution and numbers of some species of native birds in New Zealand-the bellbird for example-has been attributed to disease rather than predation. Indeed, there are examples to show that disease has deliberately been used to control some animal populations. In Australia, for instance, the introduction of the myxomatosis (多发粘液瘤病) virus has drastically reduced the rabbit population in many areas, although increasing resistance to the disease is becoming apparent. Attempts to introduce myxomatosis into New Zealand as a means of rabbit population control have failed, mainly because the species of flea and mosquito that transmit the disease are absent in this country.
Research is currently being carried out to discover whether selected strains of virus can be used to control pathogenic bacteria that have developed a resistance to drugs. It is hoped that the virus will parasite (寄生) and kill the bacteria without harming the organism that the bacteria has infected.
Why is the mixed planting of trees of the same species advocated in modern orchards and forests？

A. Because mixed forests and orchards are the recognized procedures these days.
Because trees of same species may spread disease.
C. Because orchards and forests are modern.
D. Because trees planted crowdedly do not have enough room to develop their roots.

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听力原文： Thomas Edison is a well known American inventor. He was taught by his mother when he was a child. Later he learned things by himself by reading and experimenting. He built a lab for himself to work in, and he worked very hard in his sixty years of scientific activities. He made over a thousand inventions. Few inventors in the world have had such great success.
Edison's first invention was made in 1868. He was then a telegraph operator. He wished to work out a new method to improve the old telegraph system because it was impossible at that time for the system to send more than one message along the same line at the same time. He read all the works of Faraday, another great scientist, before starting his invention. Sometimes he didn't go to bed and didn't even stop to eat. He thought he had very much to do and there was no time to lose. Days and nights he was reading and reading. After he read through Faraday's writings, he began his experiments. A few months later he succeeded in building a double transmitter and improved the old telegraph System.
(30)

A. He went to a famous school.
B. He was taught by his mother.
C. His parents employed a good teacher to teach him.
D. He was taught by his father.

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听力原文：W: John must be joking when he said he planned to sell his shop to go to university.
M: Don't be so sure. I don't know how many times he's told me he wishes to study some professions instead of going into business.
Q: What does the man mean？
(16)

A. He is sure that John is joking.
B. He believes John may sell his shop.
C. He thinks John wants to go to university.
D. He thinks John has already studied some profession.

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听力原文：W: Have you heard about the new fitness center they're building on the campus？
M: Yeah, I can hardly wait for it to open.
Q: What does the man mean？
(19)

A. The center has just opened.
B. He's looking forward to using the center.
C. The door to the fitness center is locked.
D. There are long lines to get into the fitness center.

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The applicants who go to interviews with a do-or-die attitude seldom win a job offer.

A. Y
B. N
C. NG

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A. Because mixed forests and orchards are the recognized procedures these days. Because trees of same species may spread disease. C. Because orchards and forests are modern. D. Because trees planted crowdedly do not have enough room to develop their roots.

听力原文：W: John must be joking when he said he planned to sell his shop to go to university.M: Don't be so sure. I don't know how many times he's told me he wishes to study some professions instead of going into business.Q: What does the man mean？(16)

听力原文：W: Have you heard about the new fitness center they're building on the campus？M: Yeah, I can hardly wait for it to open.Q: What does the man mean？(19)

The applicants who go to interviews with a do-or-die attitude seldom win a job offer.

A. Because mixed forests and orchards are the recognized procedures these days.
Because trees of same species may spread disease.
C. Because orchards and forests are modern.
D. Because trees planted crowdedly do not have enough room to develop their roots.

听力原文：W: John must be joking when he said he planned to sell his shop to go to university.
M: Don't be so sure. I don't know how many times he's told me he wishes to study some professions instead of going into business.
Q: What does the man mean？
(16)

听力原文：W: Have you heard about the new fitness center they're building on the campus？
M: Yeah, I can hardly wait for it to open.
Q: What does the man mean？
(19)