1、大学英语六级模拟试卷 787(无答案)一、Part I Writing (30 minutes)1 For this part, you are allowed 30 minutes to write a short essay entitled My Views on Remedial Examinations. You should write at least 150 words based on the outline given in Chinese below:1. 补考是大学教育的一部分2. 我对补考的看法3. 如何发挥补考的作用My Views on Remedial Exam
2、inations二、Part II Reading Comprehension (Skimming and Scanning) (15 minutes)Directions: In this part, you will have 15 minutes to go over the passage quickly and answer the questions attached to the passage. For questions 1-4, mark:Y (for YES) if the statement agrees with the information given in th
3、e passage;N (for NO) if the statement contradicts the information given in the passage;NG (for NOT GIVEN) if the information is not given in the passage.2 Earth: Melting in the Heat?Glaciers are melting; the ice caps are disappearing into the oceans; sea levels may rise by many meters as a consequen
4、ce. Indigenous (本土的) Arctic peoples will find their food stocks gone, while fresh water supplies in Asia and south America will disappear as the glaciers which provide them melt away; penguins, polar bears and seals will find their habitats gone, their traditional lives unlivable.But how realistic i
5、s this picture? Is the worlds ice really disappearing, or is it unscientific hot air?A European satellite named Cryosat was designed to provide definitive answers to some of these questions. A launcher fault destroyed the mission in October 2005, but the European Space Agency has approved a replacem
6、ent. In the meantime, here is our global snapshot.The AntarcticHuge, pristine (质朴的), dramatic, unforgiving-the Antarctic is where the biggest of all global changes could begin.There is so much ice here that if it all melted, sea levels globally would rise hugelyperhaps as much as 80m. Say goodbye to
7、 London, New York, Sydney, Bangkok in fact, the majority of the worlds major cities.But will it happen? Scientists divide the Antarctic into three zones: the east and west Antarctic ice sheets; and the Peninsula, the tongue of land which points up towards the southern tip of South America.“Everybody
8、 thinks that the Antarctic is shrinking due to climate change, but the reality is much more complex,“ says David Vaughan, a principal investigator at the British Antarctic Survey in Cambridge, U.K. “Parts of it appear to be thickening as a result of snowfall increases, but the Peninsula is thinning
9、at an alarming rate due to warming. The West Antarctic sheet is also thinning, and were not sure of the mason why.“On the UpTemperatures in the Peninsula appear to be increasing at around twice the global averageabout 2 over the last 50 years. Those figures are based on measurements made by instrume
10、nts at scientific stations.Earlier this year, David Vaughans group published research showing that the vast majority of glaciers along the Peninsula87% of the 244 studiedare in retreat. The ice dumped into the ocean as the glaciers retreat should not make much difference to global sea levelsperhaps
11、a few centimeters.More worrying, potentially, are the vast ice sheets covering the rest of Antarctica. Making temperature measurements for the continent as a whole is difficult; it is a vast place-more than 2,000 km across-them are few research stations, and temperatures vary naturally by 23 from ye
12、ar to year. But measurements indicate that in the west, reciting is underway.“About one-third of the West Antarctic ice sheet is thinning,“ says Dr. Vaughan, “on average by about 10cm per year, but in the worst places by 34m per year.“The rock on which the West Antarctic ice rests is below sea level
13、, and British Antarctic Survey researchers believe the thinning could be due to the ice sheet melting on its underside.“It may be that the ocean is warming and thats causing the ice to melt, but there may be other reasons as well; for example, theres lots of volcanism in that area and so that could
14、change how much heat is delivered to the underside of the ice sheet.“ Cryosat should help to pin down what is happening at the West Antarctic fringe. The radar altimeters on board its predecessors ERSI and ERS2 have been unable to map the steep slopes at the coast, whereas Cryosats instrument should
15、 be able to cope.If the entire West Antarctic ice sheet did melt, sea levels globally would rise, by around 5m. But at the moment, there is no sign of that happening.One recent scientific paper attempted to calculate probabilities for how much West Antarctic melting would contribute to global sea-le
16、vel rises during this century. The conclusions: a 30% probability of a 20 cm rise, and a 5% chance of a 1m rise.Eastern MassAnd what of the big monster, the much larger East Antarctic sheet? A recent study using altimeter data suggested it is getting thicker, by about 1.8 cm/yr; another, using the g
17、ravity satellite mission Grace indicates its mass remains stable. But could rising temperatures in time drain the ice away?“It is net going to happen on any realistic human timescale,“ says David Vaughan. “Its so cold that you could raise temperatures by 510 without having much of an impact; its on
18、rock above sea level, so warming in the ocean cant affect it.“Largely insulated from global trends and so big as to generate its own climatic systems, most of Antarctica appears to be immune to the big melt for now, though answers to what is happening in the west are eagerly awaited.The ArcticAt the
19、 top of the world, the Arctic is a region built on water. Around the Noah Pole is ocean, with ice floes crowding in each winter and thinning again in the summers.In September, we learned from scientists at the U.S. National Snow and Ice Data Center that the extent of ocean covered by ice is getting
20、smaller each year, the current rate of shrinkage they calculate at around 8% per decade. Their projection is that within about 60 years, there will be no summer ice at all on the Arctic Ocean.“Overall, the extent has been declining, with some oscillations (摆动), since the 1970s when satellites were a
21、ble to map it,“ comments Peter Wadhams, Professor of Ocean Physics at Cambridge University, U.K., and currently at the Laboratoire Oce anographique in Villefranche-sur-mer, France. “Theres been a slow decline, but now the thinning appears to be more rapid. In the last two decades, not only has the a
22、rea shrunk but the ice has got thinner by about 40%; the prediction is that it will vanish altogether during summers in the second half of this century.“Military RecordsMeasurements of thickness come mainly from military submarines, which spent long periods under the Arctic ice during the Cold War.P
23、eter Wadhams was one of the scientists who afterwards persuaded the authorities in Britain and the United States to declassify their data.But as a method of measurement, it is far from perfect; and satellites have given only limited help. The existing satellite fleet gives good measurements of ice e
24、xtent, but is not so good at detecting thickness, partly because the orbits of satellites with radar altimeters do not cover every portion of the ocean.This data deficit has led to a rival theorythat the ice is not melting at ail; it is simply piling up in another part of the ocean, perhaps along th
25、e north Canadian coast.Peter Wadhams believes he has now disproved this idea. “We did an experiment where we installed a set of buoys (浮标) in that region which measure the thickness of the ice and transmit it back via satellite,“ he says. “The buoy sits on the ice, and as waves pass under it they ma
26、ke it rise and fall, just by a millimeter or two; measuring this allows you to calculate the thickness of the ice.“The preliminary results, announced at a scientific meeting in April 2005, show that the extra ice is not there; it really has melted away.Wider ImpactTo people living, in the region, th
27、e melting brings mixed news. Current lifestyles and staple foods will almost certainly change, but the open ocean may permit new opportunities for trade and agriculture.A bigger question is what it means for the rest of the planet. Ice reflects the suns radiation; water absorbs it. More water and le
28、ss icea lower albedo (反照率)mean that the pace of warming could increase. In this scenario, the Earth would be losing one of its “natural checks and balances“ against warminganother positive feedback mechanism.The Arctic is intimately tied to the global climate system, and disruptions here have the po
29、tential to create worldwide changesalbeit (虽然) over long timescales. Possibly the most powerful link is via the thermohaline (热盐的) circulation, the global conveyor taking warm water along ocean surfaces and returning colder water at depth.“One very sensitive place is the middle of the Greenland Sea,
30、“ says Peter Wadhams. “That has been ice-free in the summer, but usually in winter it would be covered by a lobe of ice growing out from the Greenland coast. AS it formed, it rejected salt back into the water, making the water heavier and helping it to sink. Since 1997, the ice tongue has never term
31、ed. That will be having an impact on the thermohaline circulation.“Back in geological history, about 55 million years ago, the Arctic was a warm (possibly 20C) shallow sea that would have been ice-free without the intervention of a human-enhanced greenhouse effect.Natural variations may be playing a
32、 role in the picture seen now; hut, as with other parts of the planet, it is the speed of change that alarms many researchers as much as the change itself.2 Fresh water supplies in Asia and south America is disappearing as the glaciers melt away.3 If all the ice in the Antarctic melted, global sea l
33、evels would rise hugely.4 According to David Vaughan, the Antarctic is shrinking due to climate change.5 David Vaughans group found that most of the glaciers along the Peninsula were in retreat.6 Cryosat should help figure out what is happening at the West Antarctic fringe because its radar altimete
34、rs should be able to _.7 Most of Antarctica appears to be immune to the big melt for now because its largely insulated from global trends and its so big as to generate _.8 According to scientists at the U.S. National Snow and Ice Data Center, within about 60 years, there will be _ on the Arctic Ocea
35、n.9 The existing satellites are not good at detecting the thickness of the ice partly because the orbits of satellites with _ do not cover every portion of the ocean.10 To people living in the Arctic, the melting of some glaciers may permit new opportunities for _.11 The ice tongue growing out from
36、the Greenland coast used to reject salt back into the water, making _ heavier and helping it to sink.Section ADirections: In this section, you will hear 8 short conversations and 2 long conversations. At the end of each conversation, one or more questions will be asked about what was said. Both the
37、conversation and the questions will be spoken only once. After each question there will be a pause. During the pause, you must read the four choices marked A, B, C and D, and decide which is the best answer.(A)She cant help the man out until later.(B) The task will take more time than the man thinks
38、.(C) She complains that the man should have come earlier.(D)She cant support the mans argument during his debate.(A)He doesnt know what tools to bring.(B) He doesnt mind helping the woman.(C) The woman wont have to carry tools.(D)The donkeys will carry the womans personal items.(A)The man and the wo
39、man live in different buildings.(B) The woman is upset that she wasnt invited to the party.(C) The woman is complaining about the mans carelessness.(D)The man and his friends might be louder than the woman expected they would be.(A)He majors in engineering.(B) He wasnt at the lecture at that time.(C
40、) He has only recently become interested in philosophy.(D)He thinks the woman should also attend Prof. Warners class.(A)They dont enjoy swimming.(B) They dont know how to swim.(C) Theyll swim in. the lake tomorrow.(D)They wont go swimming in the lake today.(A)Jack has made others wait before.(B) Jac
41、k has often had to wait for Shelly.(C) Jack enjoys playing tricks with others.(D)Jack doesnt usually make people wait.(A)They should buy a lot of coffee.(B) Theres room to stack up the cans of coffee.(C) They should wait for a better deal on coffee.(D)The store they are talking about is out of coffe
42、e.(A)The boss is often late for work.(B) The boss will probably discipline the woman.(C) The boss may disregard the womans lateness.(D)The boss didnt know the woman was late again.(A)Planning a trip.(B) Reading.(C) Sleeping.(D)Doing research.(A)To ask for help with anthropology assignment.(B) To see
43、 what progress hes made on his paper.(C) To discuss his trip to Mexico.(D)To bring him a message from Professor Grant.(A)He cant find enough information for his research paper.(B) He cant sleep at night.(C) He cant find a quiet place to study.(D)He cant narrow down his research topic.(A)IT industry.
44、(B) Education industry.(C) Medicine industry.(D)Engineering industry.(A)Health insurance, paid vacation, and a company vehicle.(B) Paid vacation, opportunities for advancement, and medicare.(C) Opportunities for advancement, insurance, and a free bus pass.(D)Paid vacation, opportunities for promotio
45、n, and health insurance.(A)Expanding and secure.(B) Contracting, yet stable.(C) Growing, yet uncertain.(D)Promising, yet shrinking.(A)He has a Bachelors degree.(B) He didnt finish the college.(C) He is now a college student.(D)He is now studying in a night school.Section BDirections: In this section
46、, you will hear 3 short passages. At the end of each passage, you will hear some questions. Both the passage and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A, B, C and D.(A)Soil.(B) Human population.(C) Forest.(D)Wa
47、ter.(A)By using satellite images, maps, etc.(B) By studying specific farming methods.(C) By studying the variation of human population.(D)By analyzing the quality of crops.(A)By forcing them farming.(B) By affecting the quality of soils.(C) By adding chemicals and pollute the waterways.(D)By affecti
48、ng the environments they live in.(A)It is in the Atlantic Ocean.(B) It has almost been swallowed by the sea.(C) It consists of 9 islands.(D)It is famous for its canal.(A)Its canals make it sink.(B) The sea level rises up.(C) Natural disasters of flood keep attacking the country.(D)The drinking water
49、 supply is destroyed.(A)The long history shatters its ground.(B) The canals under it begin to collapse.(C) It has been half immersed in the seawater.(D)It is flooded far mote often than before.(A)Contemporary novels(B) The influence of women writers in literature.(C) How to become a famous writer.(D)How to understand her work. (A)Materials needed for the workshop.(B) Tuition for the workshop.(C) Mr. Irvines living cost.(D)A dinner banquet after the workshop. (A)Send money to t
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