Passage Three
Questions 31 to 35 are based on the following passage.
No one knows for sure why birds migrate（定期迁徙）。 One theory of migration says that ancient birds of the northern part of the earth were forced southward during the Ice Age， when ice covered large parts of Europe， Asia and North America. As the ice melted， the birds came back to their homelands， spent the summer， and then went south again in winter. Gradually， these comings and goings became habits， and birds now migrate though much of the ice has gone.
Another theory proposes that the ancient home of all modern birds was the tropic areas. There they lived so well that the region became overcrowded. Many species had to move northward.During the summer， these birds found plenty of room and food. In winter， however， food became scarce and they had to return to the south.
A newer theory is that increasing daylight stimulates certain glands（腺） in the bird‘s body and prepares it for migration. One scientist is able to make birds migrate in midwinter by exposing them for two months to artificial daylight. Recoveries of marked birds indicate that they fly north as soon as they are set free. The conclusion is that the urge to migrate is determined by changes in the bird’s body which take place under seasonal changes in the length of daylight.
This theory would account for the fact that not all birds migrate at the same time. Each species seems to have its own schedule. The theory would also account for the regular time and routes of migration. Birds arrive at a given place year after year. Unfavorable weather delays them only a few days. Total hours of daylight， rather than weather， start them on the way.
How birds find their way to the same place year after year and why they follow their own particular route are still mysteries. They evidently do not follow known landmarks（地面标志），for many young birds migrate alone without the help of experienced adults.
31.We can conclude from the first paragraph that ______.
[A]during the Ice Age， the whole Europe was covered with ice
[B]the south used to be the homelands of all birds
[C]scientists can confidently explain why birds migrate now
[D]migration of birds can be explained by the change of ice on earth.
32.The birds mentioned in the third paragraph fly north in midwinter because ______.
[A]they are specially trained by a scientist
[B]they are affected by seasonal changes
[C]there is a change in their body temperature
[D]they are exposed to extra daylight
33.The phrase“account for”（Line 2， Para. 4） most probably means ______.
[A]indicate [B]explain [C]prove [D]provide
34.Which of the following can NOT be inferred from the passage？
[A]Birds do not migrate at the same time.
[B]Birds usually follow regular routes of migration.
[C]Each species has a special reason for migration.
[D]Birds migrate to their own particular places every year.
35.The best title for the passage is ______.
[A]Different Accounts of Migration
[B]Migration and Weather
[C]New Discovery of Bird Migration
[D]Routes of Bird Migration
PART TWO
IV.Word Spelling （10 points， 1 point for two words）
将下列汉语单词译成英语并写在答题纸上。每个词的词类和第一个字母已在答题纸上给出。首字母后的每条短线上只写一个字母。
36、微小的 37、职业员 38、机密 39、尊敬
40、邀请 41、绝望 42、勇气 43、罪犯
44、昂贵的 45、争吵 46、匆忙 47、足够的
48、残忍的 49、奇迹 50、平坦的 51、失败
52、消除 53、暂停 54、允许 55、博物馆
V.Word Form （10 points， 1 point for each）
将括号中的各词变为适当形式填入空白。答案写在答题纸上。
56.Sometimes ocean currents ______（call）“rivers in the sea”。
57.The most common use of telecommunication satellites has been for ______（transmit） telephone calls.
58. Do you know why people ate unwilling ______（discuss） insurance？
59. This is another way of saying that man‘s understanding is always ______（little） than perfect.
60.You needn‘t have left the door ______（unlock） since John has got the key.
61. Last summer I was told by a colleague that I would cool more quickly if I ______（drink） steaming hot tea rather than a cold drink.
62.What can he ______（do） at this time of the day？
63.If I ______（leave） a little bit earlier， I would have caught the plane.
64.Traditionally， all the members of an ______（extend）family lived in the same area.
65.You ______（not change） much since we met last year.
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