2. 我們都佩服他事業(yè)有成。 (admire)

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                                      C

                                  ★★★★★

             Elephants have strong defenses against cancer that can prevent it forming,say scientists. They were trying to explain why the animals have lower levels of cancer than would be expected considering their size.

             People think that every cell can become cancerous,so the more of them you have,the more likely you are to get cancer. So if an elephant has 100 times as many cells as a person,then it should be 100 times more likely to have the disease. And yet the analysis showed only 5% of elephants die from cancer compared to up to 25% of people.

            The scientists turned to elephants’ DNA. Cancer is caused by mutations (變異) in a ceir s DNA that produce faulty instructions leading to (遏制不住的) growth. But animals also have “smoke alarms” that detect the damage and lead to the cell being repaired or killed. One of these alarms is called TP53,and while humans have one TP53 gene,elephants have 20.As a result,elephants seem far keener to kill off cells.

             But Mel Greaves,from the Institute of Cancer Research in London,said, “We should focus on why humans have such high levels of cancer. In terms of adaptive mechanisms (機(jī)制) against cancer we have the same as chimps,but a lot more humans get cancer than chimps. I think the answer is that humans are completely unique as a species in having very rapid social evolution (進(jìn)化) in a short period of time." He pointed to the rise of unhealthy,cancer-causing behavior,such as obesity and sunbathing. “You’ve never seen an elephant smoke!” he added.

             In an evolutionary sense, “success” is judged by the number of kids you have rather than how long you live. Elephants have the greatest reproductive success towards the end of their lives,while humans can live for decades after we are no longer able to getting pregnant. It means there is little evolutionary pressure in humans to develop ways of preventing cancer in old age.

9. What is the text mainly about? ,

   A. When elephants will get ill.

   B. How elephants live a long life.

   C. What elephants do when having cancer.

   D. Why elephants have slight chances of getting cancer.

10. Why are elephants keener to kill off cells compared with humans?

   A. They are larger in size.

   B. They have a unique alarm.

   C. They have more TP53 genes.

   D. They have healthier eating habits.

11. In the eyes of Greaves, .

   A. chimps get more cancer than humans

   B. humans* unhealthy behavior increases cancer risk

   C. chimps have better adaptive mechanisms than humans

   D. elephants have more rapid social evolution than chimps

12. When elephants become old,they will .

   A. fall into bad habits

   B. suffer from various diseases

   C. go on producing baby elephants 

   D. have less evolutionary pressure

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科目:高中英語 來源: 題型:

ask Ⅰ.Read the text and fill in the blanks in the chart.

1.2.3.4.5.6.7.8.9.10.

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科目:高中英語 來源: 題型:

1. .兩年前她靠做自由撰稿記者來維持生計(jì)。

She    as a freelance journalist

two years ago.

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科目:高中英語 來源: 題型:

II.用括號內(nèi)單詞的正確形式填空。

1. There were wild street (celebrate) When England won the Cup.

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3. He founded the charity in memory his wife.

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4. Joy   (may / will) take early retirement this year. She hasn’t decided yet.

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11. If you want to take photos here,you (can/ should) ask permission or we might get into trouble.

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IV.選用方框內(nèi)合適的選項(xiàng)完成下面對話(有兩個(gè)多余選項(xiàng)) 。

   A. I'm looking forward to it.

   B. What can I do for you? c. Hang on,please.

   D. I'd love to.

   E. It's a pleasure.

   F. I think I've already got something scheduled.

Jack: Good morning. May I speak to Carl?

This is Jack.

Sophia: This is Sophia. 1. I'11 look for

Carl and tell him you are on the phone. Jack: OK. Thank you so much.

Sophia: YouJ re most welcome.

Carl: Carl speaking.

Jack: Hello,Carl. We’re planning to give a

dinner some day next week. Would you like to join US?

Carl: Well,2. When?

Jack: How about Thursday?

Carl: I'm afraid I can't make it on Thursday.

I'11 be busy preparing my lecture.

Jack: Are you free Friday?

Carl: Friday sounds good. 3. Thank

you for your invitation.

Jack: 4.

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