1、大学英语四级改革适用（阅读）模拟试卷 86及答案与解析 Section C 0 The Earth has been stripped of up to 90% of its species five times before in the past 450 million years. Now its about to happen againand this time theres no rogue asteroid(小行星 )to blame. One of the first great rules of terrestrial biology is that no species i
2、s forever. The Earth has gone through five major extinction events before. The result of all of the extinctions was the same: death, a lot of it. As increasingly accepted theories have arguedand as the Science papers show we are now in the midst of the sixth great extinction, the unsettlingly-named
3、Anthropocene(人类纪 ), or the age of the humans. As the authors of all this loss, we are doing our nasty work in a lot of ways. Overexploitationwhich is to say killing animals for food, clothing or the sheer perverse pleasure of itplays a big role. So we get elephants slaughtered for their tusks, rhino
4、s poached(偷猎 )for their horns and tigers shot and skinned for their pelts, until oops no more elephants, rhinos or tigers. Habitat destruction is another big driver, particularly in rainforests. And you don t even have to chop or burn an ecosystem completely away to threaten its species; sometimes a
5、ll it takes is cutting a few roads across it or building a few farms or homes in the wrong spots. Then too there is global warming, which makes once-hospitable habitats too hot or dry or stormy for species adapted to different conditions. Finally, as TIMEs Bryan Walsh wrote in last week s cover stor
6、y, there are invasive speciespests like the giant African snail, the lionfishwhich hitch a ride into a new ecosystem on ships or packing material, or are brought in as pets, and then reproduce wildly, crowding out native species. It oughtn t to take appealing to our self-interest to get us to quit m
7、aking such a mess of what we re increasingly coming to learn is an exceedingly destructible world. But it s that very self-interest that led us to make that mess in the first place. We can either start to change our ways, or we can keep going the way we areat least until the Anthropocene extinction
8、claims one final species: our own. 1 The first sentence in the first paragraph doesn t indicate that_. （ A） the species on earth have decreased 90% now （ B） the past 450 million years have witnessed extinction several times （ C） every extinction has a 90% species decrease （ D） the earth has experien
9、ced five great extinction 2 The sentence “this time there s no rogue asteroid(小行星 )to blame“ means_. （ A） people blamed asteroids because they are too naughty （ B） people feel pity about not having an asteroid to blame （ C） the earth will experienced another extinction because of the asteroids （ D）
10、the asteroids once served as the reason of the past extinction 3 What is false about the reasons of great extinction? （ A） Killing the animals for food caused the extinction. （ B） Some species died out probably just because of a road. （ C） Animals are sensitive to new environment. （ D） Many species
11、extinct because of a climate change. 4 According to the Bryan Walsh s view, which statement is NOT correct? （ A） The local species extinct because the ecosystem is too crowd. （ B） The number of the invasive species increases easily. （ C） The invasive species are from other places. （ D） The invasive
12、species killed the local animals, which causes the extinction. 5 What is the best title for this passage? （ A） What Causes The Great Extinction? （ B） The Sixth Great Extinction Is Underway-And Were to Blame （ C） The End of the Anthropocene （ D） Quit Seeking Self-interest 5 A decade ago, the idea tha
13、t the planet was warming up as a result of human activity was largely theoretical. We knew that since the Industrial Revolution began in the 18th century, factories and power plants and automobiles and farms have been loading the atmosphere with heat-trapping gases, including carbon dioxide and meth
14、ane(甲烷 ). But evidence that the climate was actually getting hotter was still murky. Not anymore. As an authoritative report issued a few weeks ago by the United Nations-sponsored Intergovernmental Panel on Climate Change makes plain, the trend toward a warmer world has unquestionably begun. Worldwi
15、de temperatures have climbed more than 0.5 over the past century, and the 1990s were the hottest decade on record. After analyzing data going back at least two decades on everything from air and ocean temperatures to the spread and retreat of wildlife, the IPCC asserts that this slow but steady warm
16、ing has had an impact on no fewer than 420 physical processes and animals and plant species in all countries. Glaciers(冰川 ), including the legendary snows of Kilimanjaro, are disappearing from mountaintops around the globe. Coral reefs are dying off as the seas get too warm for comfort. Drought is t
17、he norm in parts of Asian and Africa. El Nino(厄尔尼诺 )events, which trigger devastating weather in the eastern Pacific, are more frequent. The Arctic permafrost(永久冻土带 )is starting to melt. Lakes and rivers in colder climates are freezing later and thawing earlier each year. Plants and animals are shif
18、ting their ranges pole-ward and to higher altitudes, and migration patterns for animals as diverse as polar bears, butterflies and beluga whales are being disrupted. 6 The problem of global warming_. （ A） has been predicted since the Industrial Revolution began （ B） was noticed 10 years ago as a rea
19、listic threat （ C） has nothing to do with human activity （ D） was theoretical 10 years ago but is not now 7 According to the United Nations-sponsored Intergovernmental Panel on Climate Change,_. （ A） it is doubtful that worldwide global warming has begun （ B） people should not show concern about glo
20、bal warming （ C） it is obvious that the world has started getting warmer and warmer （ D） we should carry out more research to prove the effects of global warming 8 Temperatures all over the world_. （ A） rose 5C in the 1990s （ B） were the highest in 1990s （ C） are recorded on file to research global
21、warming （ D） either increase or decrease depending on the location 9 What has happened in parts of Asian and Africa? （ A） The abnormal weather makes animals move to other areas. （ B） The surface of the sea has risen over the past century. （ C） The summer comes earlier, and the hot weather lasts long
22、er. （ D） The land is getting drier, and that makes crops easy to grow. 10 What is the best title for the passage? （ A） Life in the Greenhouse （ B） How Does Our Planet Get Warmer? （ C） We Are Making the World Warmer （ D） Everything Is Melting 10 Children who spend more than two hours a day at a compu
23、ter or watching television are more likely than others to have mental problems, scientists say. Researchers found that 11-year-olds who spent several hours in front of a screen each day did worse on mental health tests, no matter how much physical exercise they got. The University of Bristol study,
24、published in Pediatrics, involved more than 1,000 children aged about 10. They also had the kids fill out questionnaires designed to gauge the kids emotional well-being and behavior. The questionnaires contained 20 questions covering five sectionsemotional difficulties, conduct problems, hyperactivi
25、ty or inattention, friendships and peer groups and problems relating to friends and peer groups. The study found no direct evidence that sitting in front of a screen actually causes mental health problems. Instead, it suggests that children with difficulties, such as extreme shyness, are more likely
26、 to choose TV or computer games than sociable activities. In the study, children were asked whether they agreed, disagreed or somewhat agree with a list of statements, including, “I generally play alone or keep to myself and, “I am often unhappy or tearful“. They were also asked how much exercise th
27、ey took and how long they spent at a TV or computer screen. According to the study, children who spent more than two hours a day at a screen had a 60% higher risk of mental problems than children who spent fewer viewing hours. The risk was only slightly higher in children who did little or no exerci
28、se. “Physical activity is good for health in many ways, but it cant make up for long hours of screen viewing. Parents should consider limiting their children s screen viewing to no more than 2 hours a day,“ said the study organizer, Angie Page. Previous studies have raised concerns that watching too
29、 much television can affect childrens behavior in later life. A Canadian study found that those who watched most TV as young children performed worse at school, ate more junk food and had more trouble concentrating. 11 What information can we get about the University of Bristol study? （ A） The resul
30、ts of it have been published. （ B） All kids who take part in the study had an interview. （ C） The questionnaires of it contained five questions. （ D） It was done by an elementary school. 12 What is the passage mainly about? （ A） It describes the reasons people watch television. （ B） It reports the f
31、indings of a scientific study. （ C） It discusses ways to improve children s physical health. （ D） It advises parents on raising their children. 13 How did the researchers carry out the study? （ A） By reviewing childrens records online. （ B） By interviewing children s parents. （ C） By watching childr
32、en in their home. （ D） By asking children questions. 14 Which of the children behavior below leads to the highest risk of the mental problems, according to the University of Bristol study? （ A） Playing computer every day. （ B） Watching TV 3 hours per day. （ C） Doing few physical activities. （ D） Own
33、ing few friends. 15 How can children improve mental health according to the passage? （ A） By limiting TV and computer use to less than two hours a day. （ B） By getting more physical exercise. （ C） By playing more educational computer games. （ D） By going to bed earlier each night. 15 Millions of Ame
34、ricans lie awake at night counting sheep, or have a stiff drink or pop an allergy pill, hoping it will make them drowsy. But experts agree all that self-medicating is a bad idea, and the causes of chronic insomnia remain mysterious. Almost a third of adults have trouble sleeping, and about 10 percen
35、t have symptoms of daytime impairment that signal true insomnia. Sufferers readily cite the resulting problems: walking around in a fog, as memory and other cognitive functions slowly. Dozing off at the wheel or at work. Depression. Lack of energy. But for all the complaints, scientists know surpris
36、ingly little about what causes chronic insomnia, its health consequences and how best to treat it, a panel of specialists brought together by the National Institutes of Health concluded Wednesday. Two things are clear, the panel found: Chronic insomnia is a major public health problem. And too many
37、people are using unproven therapies, even while there are a few treatments that do work. Among the panel s findings: Cognitive / behavioral therapya psychology-based treatment that trains people to reduce anxiety and take other sleep-promoting stepsis very effective, and doesnt cause side effects. B
38、ut it can be hard to find health providers trained in the techniques. Insomniacs should check with board-certified sleep specialists and psychologists. Newer prescription sleep pills called Sonata, Ambien and Lunesta work without many of the side-effect concerns of older agents known as benzodiazepi
39、nes(苯二氮类 镇静药 ). One study of Lunesta showed effectiveness with six months of use, but more research on long-term use of all three is needed, as chronic insomnia can linger for years. The most commonly used treatments are alcohol and over-the-counter sedating antihistamines(抗组胺剂 )like Benadryl. Alcoh
40、ol use actually disrupts quality sleep, and antihistamines can cause lingering daytime sedation and other cognitive problems. The most common prescription insomnia medicine is an older, sedating antidepressant called trazodone, even though theres no good evidence that it offers more than a two-week
41、benefit, and it comes with side effects. 16 One of most effective ways to deal with choric insomnia is_. （ A） to have a stiff drink （ B） to pop an allergy pill （ C） to sleep and get up early （ D） Cognitive / behavioral therapy 17 Which of the following symptoms does NOT belong to insomnia? （ A） Walk
42、ing around in a fog. （ B） Lack of energy. （ C） Nap irregularly. （ D） Cognitive functions loss. 18 The National Institutes of Health found that_. （ A） unproven therapies are commonly used by people （ B） chronic insomnia is just a minor healthy problem （ C） the side effects of cognitive/behavioral the
43、rapy deserve our attention （ D） dietary supplements can be introduced to insomnia sufferers 19 “over-the-counter“ in Linel, Para.6 means_. （ A） non-prescriptional （ B） counter offering （ C） cheap and easy-to-get （ D） illegal 20 From the passage we can infer that_. （ A） unproven medicines cannot treat chronic insomnia at all （ B） insomnia sufferers have found curable medicines （ C） sleep specialists and psychologists cannot be trusted （ D） chronic insomnia still baffles sleep experts 大学英语四级改革适用（阅读）模拟试卷 86答案与解析
