1、大学英语四级（ 2013年 12月考试改革适用）模拟试卷 216及答案与解析 一、 Part I Writing 1 For this part, you are allowed 30 minutes to write a letter to send your apologies to one of your teachers because you were late. You should write at least 120 words but no more than 180 words. Section A （ A） They are safe in daily use. （ B）
2、 They can be put on skins except faces. （ C） No chemicals should be used in daily life. （ D） Children should not use them. （ A） To inspect harmfulness of chemical mixtures. （ B） To prove chemicals are harmless. （ C） To produce safe chemicals. （ D） To study chemical compositions. （ A） They are rare s
3、pecies. （ B） They protect the environment. （ C） They pollinate crops and wild plants. （ D） They protect crops and wild plants. （ A） Chemicals should be used as many as possible. （ B） Chemicals should be used only if necessary. （ C） Chemicals should be used as few as possible. （ D） Chemicals should b
4、e used once a month. （ A） In Australia and Africa. （ B） In Austria and Africa. （ C） In Australia and America. （ D） In Austria and America. （ A） Better medical equipment. （ B） More health care. （ C） Better education. （ D） More job chances. （ A） Its about 2,500 pounds. （ B） Its about 2,500 dollars. （
5、C） Its about 250 pounds. （ D） Its about 250 dollars. Section B （ A） The number of families is reduced a lot. （ B） More young people seldom stay at home. （ C） Relatives seldom live in the same place. （ D） The family members live in the same place. （ A） She wishes her parents live with her. （ B） She w
6、ishes her parents live alone. （ C） She wishes her parents live in a retirement room. （ D） She wishes her parents live with her siblings. （ A） He is always in trouble at home. （ B） He is reluctant to live with his parents. （ C） He often fights with other persons. （ D） He doesnt study hard. （ A） He li
7、kes living alone. （ B） His house is far from his parents house. （ C） He is busy with his business. （ D） He always quarrels with his parents. （ A） He is looking for a job. （ B） He is looking for a house. （ C） He is looking for a roommate. （ D） He is looking for an agent. （ A） A roommate who does not
8、snore. （ B） A roommate who does not smoke. （ C） A roommate who is very tidy. （ D） A roommate who loves studying. （ A） A flat with two bedrooms. （ B） An unfurnished apartment. （ C） A well-decorated apartment. （ D） A furnished bedroom in a shared flat. （ A） Help do housework. （ B） Bargain with the lan
9、dlord. （ C） Agree to share with others. （ D） Sign a contract for two years. Section C （ A） They cant lose weight. （ B） They can lose weight by cutting calories or exercising. （ C） They really cant keep the weight off. （ D） They should be on a diet to lose weight. （ A） Senior people are less likely t
10、o gain weight. （ B） Senior people are more likely to gain weight. （ C） Once people get fat, they will suffer various problems. （ D） Once people get fat, they gain weight steadily. （ A） It may have a negative influence. （ B） It plays a very significant role. （ C） It is meaningless. （ D） It can have a
11、 positive impact. （ A） Prevent the students doing any movement. （ B） Give students more time to rest. （ C） Bring students more activities. （ D） Adopt the same teaching plan for a long time. （ A） It can help teachers interact with the students. （ B） It just shows the words to students. （ C） It can re
12、duce the dust in the classroom. （ D） It can save teachers time. （ A） Students ability to study. （ B） Students ability to do activities. （ C） Students ability to maintain attention. （ D） Students ability to communicate with others. （ A） Pot using. （ B） Wet cloth. （ C） Sand. （ D） Temperature. （ A） Peo
13、ple who eat spoiled food may get sick. （ B） Farmers have to throw away spoiled products. （ C） Farmers have to sell the spoiled products quickly at a low price. （ D） People need money to dispose of the spoiled food. （ A） By electricity. （ B） Through an evaporation process. （ C） Through a freezing pro
14、cess. （ D） With the help of some special bacteria. （ A） He sold his invention to make money. （ B） He preferred invention to teaching. （ C） He was honored with an award for his teaching method. （ D） He financed 5,000 pot-in-pot systems to help people. Section A 26 Is technology changing our brains? A
15、 new study adds to a growing body of research that says it is. According to the study, a【 C1】 _shift in how we gather information and communicate with one another has touched off an era of rapid evolution that may【 C2】 _change the human brain as we know it. The impact of technology on our brain shou
16、ld not come as a【 C3】 _. Professional musicians have more gray matter in brain regions【 C4】 _for planning finger movements. And athletes brains are bulkier in areas that【 C5】_hand-eye coordination. Thats because the more time you devote to a specific activity, the stronger the neural(神经系统的 )pathways
17、 responsible for executing that activity become. So it makes【 C6】 _that people who process a constant stream of digital information would have more neurons dedicated to filtering(过滤 )that information. To see how the Internet might be rewiring us, the brains of 24 adults were【 C7】_as they performed a
18、 simulated Web search, and again as they read a page of text. During the Web search, those who reported using the Internet【 C8】 _in their everyday lives showed twice as much signaling in brain regions responsible for decisionmaking and complex reasoning, compared with those who had【 C9】_Internet exp
19、osure. The findings suggest that Internet use enhances the brains【 C10】 _to be stimulated, and that Internet reading activates more brain regions than printed words. A)abundant F)limited K)scarcely B)capacity G)monitored L)sense C)control H)regularly M)stability D)dramatic I)responsible N)surprise E
20、)immediately J)restrain O)ultimately 27 【 C1】 28 【 C2】 29 【 C3】 30 【 C4】 31 【 C5】 32 【 C6】 33 【 C7】 34 【 C8】 35 【 C9】 36 【 C10】 Section B 36 Weve Been Imagining Mountains All Wrong, Say Scientists A)From the simplest sketches to the most advanced scientific models, illustrations of mountains pretty
21、much all look the same. Their classic pyramid form, wider at the bottom and narrowing all the way up to the top, has been ingrained in the human mind, and scientists have always assumed that the land area in mountain ranges decreases the higher you climb. Until now, that is. B)New research published
22、 Monday in Nature Climate Change reveals a surprising discovery that not only changes the way we think about mountains but could also have big implications for how we understand, monitor and protect the organisms that call them home. It turns out mountain ranges dont just come in the familiar pyrami
23、d formin fact, most of them have a different shape entirely. C)Researchers Morgan Tingley and Paul Elsen used satellite data on mountain ranges from around the globe to analyze how the amount of the land area changed with increasing elevation(海拔 ). They learned that pyramidal mountain ranges account
24、 for just 32 percent of the mountain ranges on Earth. Of the remaining mountain ranges, six percent have an inverse, or upside-down, pyramid form, with the land area increasing toward the top; 23 percent have an hourglass(沙漏 )shape, being wider and at the bottom and top and pinched(挤压 )in the middle
25、; and 39 percent have a diamond form, with less land areas at the top and bottom and more available in the middle. D)“I did expect that wed see some patterns that were not this classic pyramid,“ says Elsen, lead author and PhD student in Princeton Universitys ecology and evolutionary biology departm
26、ent. In fact, Elsen got interested in conducting the study while doing field research in the Himalayas. He noticed that as he hiked to the tops of the mountains, the land area seemed to increase, rather than decrease, at high elevations. Still, he says, “I had no idea that pyramid mountains would be
27、 the exception to the rule.“ E)Its hard to tell the true form of a mountain range just by looking at any given mountain peak, since most individual mountains still come to a point at the very top. But mountain ranges are so big, and their topography(地形 )so complex, that it would be impossible to obs
28、erve their true shapes just by looking at them. Thats why the researchers had to analyze satellite data, looking at the total surface area in relation to elevation across the whole mountain range, to complete their study. The way the land area is distributed on a landscape scalewhether the greatest
29、area lies at the top, bottom or in the middle when you take into account all the slopes, ravines and plateaus that make up the mountainsis what determines a mountain ranges designation as a pyramid, inverse pyramid, diamond or hourglass. F)The finding doesnt just flip our view of mountain topography
30、. More importantly, it changes our understanding of how climate change can affect mountain-dwelling species, the authors say. Organisms that live on mountains are in a particular pickle when it comes to climate change. These species tend to be highly specialized and do best in particular habitats an
31、d narrow temperature ranges. As global temperatures rise, the best way to find cooler spots is to move higher up on the mountain. But in pyramidal mountain ranges, which get narrower toward the top, moving higher also means losing the land area. Having less available space can cause populations to s
32、hrink and can put them at an increased risk of dying out entirely. G)But Elsen and Tingleys research shows that the pyramid model doesnt hold true for all, or even most mountain ranges, meaning space shortages might not always fall where scientists think they do. In hourglass mountains, for example,
33、 the most constricted(狭窄的 )space will be in the middle of the mountain, rather than at the top. On the other hand, species on diamond mountains will see the widest spaces in the middle. And species on inverse pyramids will enjoy increasing land areas all the way up to the top of the mountain. H)“I t
34、hink this is critical information that will really inform our understanding of mountain species,“ says Robert Guralnick, a biodiversity scientist and curator(馆长 )at the University of Floridas natural history museum, who was not involved with the study. “The models weve been using are typically that
35、mountain ranges are narrowing toward the top. “ More realistic models and a better understanding of mountain topography can help conservationists make better decisions when monitoring and managing mountain species, the papers authors say. “This is absolutely an important study for informing our cons
36、ervation policy,“ Elsen says. Knowing where the land area is likely to be scarce can help conservationists target the right places and the right species. I)In some cases, new knowledge could even indicate that climate change doesnt threaten a species in quite the way scientists thought. The Himalaya
37、n monal, for example, is a colorful bird that lives in the Himalayan mountains, which have the hourglass form. Currently, the bird prefers an elevation thats right in the middle of the hourglass, says Morgan Tingley, senior author and assistant professor of ecology and evolutionary biology at the Un
38、iversity of Connecticut. So space may be pinched for it now, but if warming temperatures force the bird into higher elevations, it will likely enjoy more space as it moves upward. J)On the other hand, a bright little bird called the beautiful nuthatchwhich is already classified as a vulnerable speci
39、es by the International Union for Conservation of Naturelives just below the pinched part of the hourglass. If it were to flee to higher ground, it would lose the land area. “This current research is showing that there are potentially optimistic futures for some species, and its also highlighting th
40、ese bottleneck zones,“ Elsen says. K)The research is also relevant for species that move downslope in response to climate change, chasing the increased precipitation that comes with warmer temperatures. Before now, most scientists might have assumed that any species moving downhill would be able to
41、take advantage of greater and greater land areas as it moved along. Now we know that in certain mountain ranges, these species may actually encounter a shortage in space as they move toward the base of the mountain, and their populations may shrink as a result. 37 As for inverse pyramidal mountains,
42、 species have wider land areas all the way up. 38 The Himalayas have got wider land areas at higher elevations. 39 The mountain areas are too large and complex for researchers to observe so that satellites have to be used in order to get exact data. 40 Most people have got the same idea about how a
43、mountain looks like, which is a typical pyramid form. 41 The more conservationists know about mountain models and topography, the better they can monitor and manage mountain species. 42 In pyramidal mountain ranges species that move to a higher and cooler place are faced with the lack of the land ar
44、ea and finally the risk of extinction. 43 Except for the pyramid form, mountain ranges have got other forms like the inverse pyramid form, an hourglass shape and a diamond form. 44 The finding changes our understanding of how climate change can affect species living in the mountains. 45 The current
45、research indicates that there are good opportunities as well as some dangers for some mountain species. 46 That scientists used to think that species moving downhill would live in a wider area may not be true according to the current knowledge of different mountain ranges. Section C 46 You may know
46、the feeling. Its the late afternoon, and you still havent left the house. Youve spent the last several hours on your phone, scrolling through your Facebook news feed, refreshing Twitter and watching YouTube videos. A smartphone might feel like its keeping you connected, but it can also be a way of s
47、ecluding yourself. Data from a recent study conducted by researchers at Northwestern Universitys Feinberg School of Medicine found that the scenario described abovehigh volume of phone use and a static(静止 的 )geographic locationcould be linked to depression. The study, published in The Journal of Med
48、ical Internet Research, also found that depressed people, on average, spend more time on the phone than non-depressed people. “People are likely, when on their phones, to avoid thinking about things that are troubling, painful feelings or difficult relationships,“ said David Mohr, one of the studys
49、senior authors and a professor of behavioral psychology at Northwestern, in a statement. “Its an avoidance behavior we see in depression.“ Mohr also pointed out that depressed people tend to withdraw emotionally and avoid going outbehaviors that are arguably facilitated by the constant entertainment stream available on smartphones. The studys participants consisted of a mix of people with and without prior depression. They completed a questionnaire describing their symptoms before agreeing
