1、雅思（阅读）模拟试卷 79及答案与解析 0 Snow-makers Skiing is big business nowadays. But what can ski resort owners do if the snow doesn t come? A In the early to mid twentieth century, with the growing popularity of skiing, ski slopes became extremely profitable businesses. But ski resort owners were completely depe
2、ndent on the weather; if it didnt snow, or didnt snow enough, they had to close everything down. Fortunately, a device called the snow gun can now provide snow whenever it is needed. These days such machines are standard equipment in the vast majority of ski resorts around the world, making it possi
3、ble for many resorts to stay open four months or more a year. B Snow formed by natural weather systems comes from water vapour in the atmosphere. The water vapour condenses into droplets, forming clouds. If the temperature is sufficiently low, the water droplets freeze into tiny ice crystals. More w
4、ater particles then condense onto the crystal and join with it to form a snowflake. As the snowflake grows heavier, it falls towards the Earth. C The snow gun works very differently from a natural weather system, but it accomplishes exactly the same thing. The device basically works by combining wat
5、er and air. Two different hoses are attached to the gun, one leading from a water pumping station which pumps water up from a lake or reservoir, and the other leading from an air compressor. When the compressed air passes through the hose into the gun, it atomises the water that is, it disrupts the
6、stream so that the water splits up into tiny droplets. The droplets are then blown out of the gun and if the outside temperature is below 0C, ice crystals will form, and will then make snowflakes in the same way as natural snow. D Snow-makers often talk about dry snow and wet snow. Dry snow has a re
7、latively low amount of water, so it is very light and powdery. This type of snow is excellent for skiing because skis glide over it easily without getting stuck in wet slush. One of the advantages of using a snow-maker is that this powdery snow can be produced to give the ski slopes a level surface.
8、 However, on slopes which receive heavy use, resort owners also use denser, wet snow underneath the dry snow. Many resorts build up the snow depth this way once or twice a year, and then regularly coat the trails with a layer of dry snow throughout the winter. E The wetness of snow is dependent on t
9、he temperature and humidity outside, as well as the size of the water droplets launched by the gun. Snow-makers have to adjust the proportions of water and air in their snow guns to get the perfect snow consistency for the outdoor weather conditions. Many ski slopes now do this with a central comput
10、er system that is connected to weather-reading stations all over the slope. F But man-made snow makes heavy demands on the environment. It takes about 275,000 litres of water to create a blanket of snow covering a 60x60 metre area. Most resorts pump water from one or more reservoirs located in low-l
11、ying areas. The run-off water from the slopes feeds back into these reservoirs, so the resort can actually use the same water over and over again. However, considerable amounts of energy are needed to run the large air-compressing pumps, and the diesel engines which run them also cause air pollution
12、. G Because of the expense of making snow, ski resorts have to balance the cost of running the machines with the benefits of extending the ski season, making sure they only make snow when it is really needed, and when it will bring the maximum amount of profit in return for the investment. But man-m
13、ade snow has a number of other uses as well. A layer of snow keeps a lot of the Earths heat from escaping into the atmosphere, so farmers often use man-made snow to provide insulation for winter crops. Snow-making machines have played a big part in many movie productions. Movie producers often take
14、several months to shoot scenes that cover just a few days. If the movie takes place in a snowy setting, the set decorators have to get the right amount of snow for each day of shooting either by adding man-made snow or melting natural snow. And another important application of man-made snow is its u
15、se in the tests that aircraft must undergo in order to ensure that they can function safely in extreme conditions. Reading Passage 1 has seven paragraphs A-G. Choose the correct heading for each paragraph from the list of headings below. Write the correct number(i-x)in boxes 1-5 on your answer sheet
16、. List of headings i Considering ecological costs ii Modifications to the design of the snow gun iii The need for different varieties of snow iv Local concern over environmental issues v A problem and a solution vi Applications beyond the ski slopes vii Converting wet snow to dry snow viii New metho
17、d for calculating modifications ix Artificial process, natural product x Snow formation in nature Example Answer Paragraph A v Paragraph B x 1 Paragraph C 2 Paragraph D 3 Paragraph E 4 Paragraph F 5 Paragraph G 5 Label the diagram below.Choose NO MORE THAN TWO WORDS from the passage for each answer.
18、Write your answers in boxes 6-8 on your answer sheet. The snow gun9 Dry snow is used to give slopes a level surface, while wet snow is used to increase the_on busy slopes. 10 To calculate the required snow consistency, the_and _of the atmosphere must first be measured. 11 The machinery used in the p
19、rocess of making the snow consumes a lot of _, which is damaging to the environment. 12 Artificial snow is used in agriculture as a type of_for plants in cold conditions. 13 Artificial snow may also be used in carrying out safety checks on _. 13 You should spend about 20 minutes on Questions 14-26,
20、which are based on Reading Passage 2 below. Why are so few tigers man-eaters? A As you leave the Bandhavgarh National Park in central India, there is a notice which shows a huge, placid tiger. The notice says, You may not have seen me, but I have seen you. There are more than a billion people in Ind
21、ia and Indian tigers probably see humans every single day of their lives. Tigers can and do kill almost anything they meet in the jungle they will even attack elephants and rhino. Surely, then, it is a little strange that attacks on humans are not more frequent. B Some people might argue that these
22、attacks were in fact common in the past. British writers of adventure stories, such as Jim Corbett, gave the impression that village life in India in the early years of the twentieth century involved a state of constant siege by man-eating tigers. But they may have overstated the terror spread by ti
23、gers. There were also far more tigers around in those days(probably 60,000 in the subcontinent, compared to just 3,000 today). So in proportion, attacks appear to have been as rare then as they are today. C It is widely assumed that the constraint is fear; but what exactly are tigers afraid of? Can
24、they really know that we may be even better armed than they are? Surely not. Has the species programmed the experiences of all tigers with humans into its genes to be inherited as instinct? Perhaps. But I think the explanation may be more simple and, in a way, more intriguing. D Since the growth of
25、ethology1 in the 1950s, we have tried to understand animal behaviour from the animals point of view. Until the first elegant experiments by pioneers in the field, such as Konrad Lorenz, naturalists wrote about animals as if they were slightly less intelligent humans. Jim Corbetts breathless accounts
26、 of his duels with man-eaters in truth tell us more about Jim Corbett than they do about the animals. The principle of ethology, on the other hand, requires us to attempt to think in the same way as the animal we are studying thinks, and to observe every tiny detail of its behaviour without imposing
27、 our own human significances on its actions. E I suspect that a tigers fear of humans lies not in some preprogrammed ancestral logic but in the way he actually perceives us visually. If you try to think like a tiger, a human in a car might appear just to be part of the car, and because tigers dont e
28、at cars the human is safe unless the car is menacing the tiger or its cubs, in which case a brave or enraged tiger may charge. A human on foot is a different sort of puzzle. Imagine a tiger sees a man who is 1.8m tall. A tiger is less than lm tall but he may be up to 3m long from head to tail. So wh
29、en a tiger sees the man face on, it might not be unreasonable for him to assume that the man is 6m long. If he met a deer of this size, he might attack the animal by leaping on its back, but when he looks behind the man, he cant see a back. From the front the man is huge, but looked at from the side
30、 he all but disappears. This must be very disconcerting. A hunter has to be confident that it can tackle its prey, and no one is confident when they are disconcerted. This is especially true of a solitary hunter such as the tiger and may explain why lions particularly young lionesses who tend to enc
31、ourage one another to take risks are more dangerous than tigers. F If the theory that a tiger is disconcerted to find that a standing human is both very big and yet somehow invisible is correct, the opposite should be true of a squatting human. A squatting human is half the size and presents twice t
32、he spread of back, and more closely resembles a medium-sized deer. If tigers were simply frightened of all humans, then a squatting person would be no more attractive as a target than a standing one. This, however, appears not to be the case. Many incidents of attacks on people involve villagers squ
33、atting or bending over to cut grass for fodder or building material. G The fact that humans stand upright may therefore not just be something that distinguishes them from nearly all other species, but also a factor that helped them to survive in a dangerous and unpredictable environment. Questions 1
34、4-18 Reading Passage 2 has seven paragraphs labelled A-G. Which paragraph contains the following information? Write the correct letter A-G in boxes 14-18 on your answer sheet. 14 a rejected explanation of why tiger attacks on humans are rare 15 a reason why tiger attacks on humans might be expected
35、to happen more often than they do 16 examples of situations in which humans are more likely to be attacked by tigers 17 a claim about the relative frequency of tiger attacks on humans 18 an explanation of tiger behaviour based on the principles of ethology 18 Do the following statements agree with t
36、he information given in Reading Passage 2? In boxes 19-23 on your answer sheet, write TRUE if the statement agrees with the information FALSE if the statement contradicts the information NOT GIVEN if there is no information on this 19 Tigers in the Bandhavgarh National Park are a protected species.
37、（ A） TRUE （ B） FALSE （ C） NOT GIVEN 20 Some writers of fiction have exaggerated the danger of tigers to man. （ A） TRUE （ B） FALSE （ C） NOT GIVEN 21 The fear of humans may be passed down in a tigers genes. （ A） TRUE （ B） FALSE （ C） NOT GIVEN 22 Konrad Lorenz claimed that some animals are more intelli
38、gent than humans. （ A） TRUE （ B） FALSE （ C） NOT GIVEN 23 Ethology involves applying principles of human behaviour to animals. （ A） TRUE （ B） FALSE （ C） NOT GIVEN 24 Why do tigers rarely attack people in cars? （ A） They have learned that cars are not dangerous. （ B） They realise that people in cars c
39、annot be harmed. （ C） They do not think people in cars are living creatures. （ D） They do not want to put their cubs at risk. 25 The writer says that tigers rarely attack a man who is standing up because （ A） they are afraid of the mans height. （ B） they are confused by the mans shape. （ C） they are
40、 puzzled by the mans lack of movement. （ D） they are unable to look at the man directly. 26 A human is more vulnerable to tiger attack when squatting because （ A） he may be unaware of the tigers approach. （ B） he cannot easily move his head to see behind him. （ C） his head becomes a better target fo
41、r the tiger. （ D） his back appears longer in relation to his height. 26 You should spend about 20 minutes on Questions 27-40, which are based on Reading Passage 3 below. Keep taking the tablets The history of aspirin is a product of a rollercoaster ride through time, of accidental discoveries, intui
42、tive reasoning and intense corporate rivalry. In the opening pages of Aspirin: The Remarkable Story of a Wonder Drug, Diarmuid Jeffreys describes this little white pill as one of the most amazing creations in medical history, a drug so astonishingly versatile that it can relieve headache, ease your
43、aching limbs, lower your temperature and treat some of the deadliest human diseases. Its properties have been known for thousands of years. Ancient Egyptian physicians used extracts from the willow tree as an analgesic, or pain killer. Centuries later the Greek physician Hippocrates recommended the
44、bark of the willow tree as a remedy for the pains of childbirth and as a fever reducer. But it wasnt until the eighteenth and nineteenth centuries that salicylates the chemical found in the willow tree became the subject of serious scientific investigation. The race was on to identify the active ing
45、redient and to replicate it synthetically. At the end of the nineteenth century a German company, Friedrich Bayer they were made by scientists working in the public sector. The reason for that is very simple and straightforward, Jeffreys says in his book. Drug companies will only pursue research tha
46、t is going to deliver financial benefits. Theres no profit in aspirin any more. It is incredibly inexpensive with tiny profit margins and it has no patent any more, so anyone can produce it. In fact, theres almost a disincentive for drug companies to further boost the drug, he argues, as it could po
47、ssibly put them out of business by stopping them from selling their more expensive brands. So what is the solution to a lack of commercial interest in further exploring the therapeutic benefits of aspirin? More public money going into clinical trials, says Jeffreys. If I were the Department of Healt
48、h, I would say “this is a very inexpensive drug. There may be a lot of other things we could do with it.“ We should put a lot more money into trying to find out. Jeffreys book which not only tells the tale of a wonder drug but also explores the nature of innovation and the role of big business, publ
49、ic money and regulation reminds us why such research is so important. Questions 27-32 Complete each sentence with the correct ending A-H from the box below. Write the correct letter A-H in boxes 27-32 on your answer sheet. A the discovery of new medical applications. B the negative effects of publicity. C the large pharmaceutical companies. D the industrial revolution. E the medical uses of a particular tree. F the limited availability of new drugs. G the chemical found in the willow tr
