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大学英语考试
大学英语考试
全国英语等级考试(PETS)
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大学英语六级CET6
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全国大学生英语竞赛(NECCS)
硕士研究生英语学位考试
单选题2. Don't let such a ______ matter as this come between us so that we can concentrate on the major issue.
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单选题27. Mutual respect for territorial ______ is one of the bases upon which our two countries develop relationships.
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单选题[此试题无题干]
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单选题New Discoveries of Public TransportAA new study conducted for the World Bank by Murdoch Universitys Institute for Science and Technology PolicyISTPhas demonstrated that public transport is more e
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单选题. The amount of floating plastic trapped in a north Atlantic current system hasn't got any bigger in 22 years, despite more and more plastic being thrown away. Since 1986 students taking samples of plankton (浮游生物) in the Atlantic and Caribbean Oceans have also noted when their nets caught plastic litter. Kara Lavender and colleagues at the Sea Education Association in Woods Hole, Massachusetts, analysed the data, and found that of 6,136 samples recorded, more than 60 per cent included pieces of plastic, typically just millimetres across. The areas of highest plastic concentration are within the north Atlantic sub-tropical gyre (环流), where currents gather the litter. Lavender and her team were surprised to find that the amount of floating plastic had not increased in the gyre. Although it has been illegal since the 1970s for ships to throw plastic overboard, Lavender thinks that the overall rate of plastic rubbish reaching the ocean will have increased, given the fivefold increase in global production of plastic since 1976. "Where the extra plastic is going is the big mystery," she says. Plastic resists bio-degradation and can last decades or more in the ocean. Eventually sunlight and wave motion break it into smaller pieces, which can be harmful to marine life—blocking the stomachs of fish and seabirds, for example. Some experts suggest that the plastic might be degrading into pieces small enough to pass through the 0.3-millimetre-mesh nets used in the study, or becoming coated in biofilms and sinking out of range of the nets. However it is unclear why the rate of degradation during the study period should have increased to offset the extra plastic going into the ocean. Lavender says it is unlikely that ocean currents are pushing plastic out of the gyre, although Simon Boxall of the National Oceanography Centre in Southampton, UK, who wasn't involved in the study, disagrees. He says the Atlantic gyre has an exit strategy in the form of the Gulf Stream. "We've seen high levels of plastic in the Arctic." he says. Wherever it is going at the moment, the plastic on our oceans will eventually be broken down into microscopic pieces and individual molecules whose environmental effect is unknown. "The million-dollar question is, is it causing any damage?" says Boxall. "When plastic particles get so small are they just like fibre going through the system? Some studies suggest that persistent chemicals in newer plastics function as endocrine (内分泌) disruptors and simulated hormones." And this fine-grained plastic is very long-lived. "The depressing thing is it's likely to remain in the oceans essentially forever," says Lavender.1. Kara Lavender and her colleagues had analyzed 6,136 samples of ______.
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单选题11. Often such arguments have the effect of ______ rather than clarifying the issues involved.
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单选题. Questions 20 to 22 are based on the recording you have just heard.5.
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单选题. Children who live near a main road are in greater danger of catching pneumonia (肺炎) because pollution from passing traffic damages their lungs. A leading expert in childhood breathing difficulties has made the link between exposure to particles from vehicle exhausts and a child's susceptibility to the chest infection, which can be fatal. Professor Jonathan Grigg, an honorary consultant at the Royal London Hospital and academic paedia-trician (儿科医生) at Queen Mary, University of London, made the breakthrough after studying the effect of airborne pollutants on human lung cells. Children whose home is within 100 metres of a main road could be as much as 65% more likely than others to develop pneumonia, he said. Although the disease is usually associated with the elderly, it is a significant childhood illness. Every year about 20,000 children and young people under 18 end up in hospital after contracting the condition. Children trader 12 months are the most likely to die. Of the 76 young people under 20 who died in 2008, 29 had not reached their first birthday—20 boys and nine girls—and 23 others were between one and four. "The findings strongly suggest that particles pollution is a major factor in making children vulnerable to pneumonia. We've shown a very firm link between the two. The study raises strong suspicions that particles cause pneumonia in children," said Grigg. "This is significant because pneumonia causes many admissions of previously healthy children to hospital." Some children with the disease spend several weeks in intensive care. Previous studies have blamed proximity to a main road for children having higher rates of asthma, coughs, ear, nose and throat infections. A study this month by the Boston-based Health Effects institute claimed that poisonous emissions from vehicles can speed up hardening of blood vessels, as well as worsening lung function. "Strong evidence" suggested that being exposed to traffic fumes can lead to variations in heart rate and other potentially fatal heart complaints, the study said. Exposure to the burning of wood or coal, or to tobacco smoke, can also increase a child's chances of pneumonia. One study found that secondhand smoke was to blame for 28.7% of all children under five in Vietnam who were admitted to hospital with the condition. Professor Steve Field, chairman of the Royal College of GPs, said: "We have known for some time that pollution causes chest problems, such as asthma, in both children and adults. This new research adds to the weight of evidence about the problems of air pollution, especially from cars, buses and lorries." The research underlined the need for Britain to move towards greener forms of transport in order to protect public health from traffic fumes, he suggested.1. What is taken as fatal by Professor Jonathan Grigg? ______
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单选题 He soon received promotion
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单选题. Now listen to the following recording and answer questions 23 to 25.8.
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单选题33. Millions of people around the world have some type of physical, mental, or emotional ______ that severely limits their abilities to manage their daily activities.
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单选题. The human criterion for perfect vision is 20/20 for reading the standard lines on a Snellen eye chart without a hitch. The score is determined by how well you read lines of letters of different sizes from 20 feet away. But being able to read the bottom line on the eye chart does not approximate perfection as far as other species are concerned. Most birds would consider us very visually handicapped. The hawk, for instance, has such sharp eyes that it can spot a clime on the sidewalk while perched on top of the Empire State Building. It can make fine visual distinctions because it is blessed with one million cones per square millimeter in its retina (视网膜). And in water, humans are farsighted, while the kingfisher, swooping down to spear fish, can see well in both the air and water because it is endowed with two foveae (凹窝)areas of the eye, consisting mostly of cones, that provide visual distinctions. One fovea permits the bird, while in the air, to scan the water below with one eye at a time. This is called monocular vision. Once it hits the water, the other fovea joins in, allowing the kingfisher to focus both eyes, like binoculars, on its prey at the same time. A frog's vision is distinguished by its ability to perceive things as a constant motion picture. Known as "bug detectors", a highly developed set of cells in a frog's eyes responds mainly to moving objects. So, it is said that a frog sitting in a field of dead bugs wouldn't see them as food and would starve. The bee has a "compound" eye, which is used for navigation. It has 15,000 facets that divide what it sees into a pattern of dots, or mosaic. With this kind of vision, the bee sees the sun only as a single dot, a constant point of reference. Thus, the eye is a superb navigational instrument that constantly measures the angle of its line of flight in relation to the sun. A bee's eye also gauges flight speed. And if that is not enough to leave our 20/20 "perfect vision" paling into insignificance, the bee is capable of seeing something we can't—ultraviolet light. Thus, what humans consider to be "perfect vision" is in fact rather limited when we look at other species. However, there is still much to be said for the human eye. Of all the mammals, only humans and some primates can enjoy the pleasures of color vision.1. The Snellen eye chart measures one's eyesight by ______.
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单选题. Questions 16 to 19 are based on the recording you have just heard.1.
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单选题37. There are not many teachers who are strong ______ of traditional methods in English teaching.
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单选题. Now listen to the following recording and answer questions 19 to 21.4.
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