题目内容
In July 1994, the comet(彗星) Shoemaker-Levy 9 smashed into the planet Jupiter. For the first time, humans were able to witness exactly what happens when a celestial(天空的) body collides with a planet and it quickly became clear that survival was no longer entirely a question of being the "fittest". A new factor had been introduced into evolution: the ability to survive a collision between the earth and an asteroid (小行星) or comet.To most people, the risk remains academic. With all the dangers humans face -- sickness, accidents- it is understandable that people don’t take seriously the risks posed by something that hasn’t happened for 65 million years and may not happen for another 65 million years.However, many scientists believe that collisions between the earth and celestial bodies cannot be regarded as "just another risk". The main reason for this is that no other disaster -- except perhaps a nuclear war -- has the potential to destroy human civilization completely. Even the worst floods and earthquakes affect only a very small percentage of the earth’s surface and population. But the effects of an impact caused by a celestial body of just ten kilometers in diameter would make humans extinct, along with most of the world’s other animals and plants.The danger comes from asteroids and comets which cross the earth’s orbit. Asteroids pose a greater danger because they are more numerous. Those less than 100 meters in diameter are not usually regarded as a threat bemuse most are destroyed by heat as they enter the earth’s atmosphere and so never reach the ground. It is those asteroids with diameters of one kilometer or more which pose the greatest threat. The main topic of this passage is （）.
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It had been a tiring day and I was looking forward to a quiet evening. My husband would not be back until (41) and I had decided to settle down in a comfortable chair in the living room and read a good book. I (42) the children to bed early and (43) a sandwich and a cup of coffee. Soon I was (44) comfortably with my book in front of me and the sandwich and cup of coffee (45) a tray beside me.I was just beginning to eat (46) the telephone rang. I dropped my book and hurried to answer it. (47) the time I got back to the living room, my coffee was cold. I ate the sandwich and began sipping(呷) (48) coffee with the book still open (49) the first page. Suddenly there was a loud knock (50) the front door. It startled me so (51) that I (52) some coffee on my skirt. The man (53) the door was looking for a (54) address and wanted me to give him directions. It took me a long time (55) him. After that, I sat down again and (56) to read a whole page without further interruption until the baby woke up. He started screaming at the top of his (57) , so I rushed upstairs. He was still (58) at 11 o’clock when my husband came home, I (59) something at him when he asked me (60) I had spent a pleasant evening. 55（）
As they grow older, most people wonder how increasing age will affect intelligence. Can people in middle age and beyond expect to think as effectively and to solve problems as efficiently as they have in the pastOne of the difficulties in comparing the intellectual functioning of people at different ages is the problem of cohort((具有相同特征的)一群人) effects. Different age groups in the population have experienced different historical events (wars, exposure to television, and so on) as well as changes in the general standard of living. Different scores that people of varying ages achieve on intelligence tests could be partly due to changes in diet, housing, or health care or, even more likely, to the amount and quality of education. Since the beginning of this century, there has been a trend for more people to go to school and to remain in school longer. Because it eliminates these cohort effects, a longevous (长寿的) study may be the best way to look at age-related changes in intellectual functioning.One of the few longevous studies of intellectual functioning is the Seattle Longevous Study, conducted by K. Warner Schaie and his associates. The original subjects, who ranged in age from 18 to 67, have now been tested 4 times over a 21 year period. These results have given a reasonably good picture of longitudinal(纵向的) change in cognitive abilities.The data show that there are only trivial changes in the kinds of abilities measured by intelligence tests before the age of 60, and no reliable decrease can be shown in these abilities before age 74. Although there is some decrease in measured ability in the late 60s and the 70s, it is not until age 81 that the average person falls below the middle range of performance for young adults.The data from the Seattle Longevous Study also suggest that there are very great individual differences in intellectual change throughout adulthood. Between the ages of 74 and 81, less than half the subjects showed any significant change. One important factor is health, especially the presence or absence of coronary(冠状) heart disease. Another is a high socioeconomic status, which is related not only to higher initial levels of functioning but to the maintenance of a higher level throughout life.A flexible life style in middle age, probably associated with a flexible personality style, also tends to predict high performance in old age. While some of these variables may have substantial hereditary (遗传的) elements, changes in environment and education could also be important in maintaining a higher level of functioning for many individuals. Which of the following statements is NOT true according to the passage ？（）
He stopped (for a moment) (at) the corner of the street, (wondered) which way he (should) take.（）
Directions:For Questions 6—10, you will hear a report about Valentine cards. While you listen, complete the sentences or answer the questions. Use not more than 3 words for each answer. You will hear the recording only once. Which nation is the least romantic according to the passage
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