2021宁夏GRE考试考前冲刺卷（9）.docx

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1、2021宁夏GRE考试考前冲刺卷（9）本卷共分为2大题50小题，作答时间为180分钟，总分100分，60分及格。一、单项选择题（共25题，每题2分。每题的备选项中，只有一个最符合题意） 1.A survey is a study, generally in the form of an interview or a questionnaire, that provides information concerning how people think and act. In the United States, the best-known surveys are the Gallup pol

2、l and the Harris poll. As anyone who watches the news during Line campaigns presidential knows, these polls have become an important part of political life in(5) the United States. North Americans are familiar with the many person on the street interviews on local television news shows. While such i

3、nterviews can be highly entertaining, they are not necessarily an accurate indication of public opinion. First, they reflect the opinions of only those people who appear at a certain location. Thus, such samples can be biased in favor(10)of commuters, middle-class shoppers, or factory workers, depen

4、ding On which area the newspeople select. Second, television interviews tend to attract outgoing people who are willing to appear on the air, while they frighten away others who may feel intimidated by a camera. A survey must be based on a precise, representative sampling if it is to genuinely refle

5、ct a broad range of the population.(15) In preparing to conduct a survey, sociologists must exercise great care in the wording of questions. An effective survey question must be simple and clear enough for people to understand it. It must also be specific enough so that there are no problems in inte

6、rpreting the results. Even questions that are less structured must be carefully phrased in order to elicit the type of information desired. Surveys can be indispensable sources of information, but(20)only if the sampling is done properly and the questions are worded accurately. There are two main fo

7、rms of surveys: the interview and the questionnaire. Each of these forms of survey research has its advantages. An interviewer can obtain a high response rate because people find it more difficult to turn down a personal request for an interview than to throw away a written questionnaire. In additio

8、n, an interviewer can go beyond written(25)questions and probe for a subjects underlying feelings and reasons. However, questionnaires have the advantage of being cheaper and more consistent.The word precise in line 13 is closest in meaning toAplannedBrationalCrequiredDaccurate 2. Because the low la

9、titudes of the Earth, the areas near the equator, receive more heat Than the latitudes near the poles, and because the nature of heat is to expand and move, Heat is transported from the tropics to the middle and high latitudes. Some of this heat is Moved by winds and some by ocean currents, and some

10、 gets stored in the atmosphere in(5) the form of latent heat. The term latent heat refers to the energy that has to be used to Convert liquid water to water vapor. We know that if we warm a pan of water on a stove, it will evaporate, or turn into vapor, faster than if it is allowed to sit at room te

11、mperature. We also know that if we hang wet clothes outside in the summertime they will dry faster than in winter, when temperatures are colder. The energy used in both cases to change (10) liquid water to water vapor is supplied by heatsupplied by the stove in the first case and by the Sun in the l

12、atter case. This energy is not lost. It is stored in water vapor in the atmosphere as latent heat. Eventually, the water stored as vapor in the atmosphere will condense to liquid again, and the energy will be released to the atmosphere. In the atmosphere, a large portion of the Suns incoming energy

13、is used to evaporate (15) Water, primarily in the tropical oceans. Scientists have tried to quantify this proportion of the Suns energy. By analyzing temperature, water vapor, and wind data around the globe, they have estimated the quantity to be about 90 watts per square meter, or nearly 30 percent

14、 of the Suns energy. Once this latent heat is stored within the atmosphere, it can be transported, primarily to higher latitudes, by prevailing, large-scale winds. Or it (20) can be transported vertically to higher levels in the atmosphere, where it forms clouds and subsequent storms, which then rel

15、ease the energy back to the atmosphere.Why does the author mention the stove in line 10ATo describe the heat of the SunBTo illustrate how water vapor is storedCTo show how energy is storedDTo give an example of a heat source 3. Many prehistoric people subsisted as hunters and gatherers. Undoubtedly,

16、 game animals, including some very large species, provided major components of human diets. An important controversy centering on the question of human effects on prehistoric wildlife concerns the sudden disappearance of so many species of large animals at or near the end(5) of the Pleistocene epoch

17、. Most paleontologists suspect that abrupt changes in climate led to the mass extinctions. Others, however, have concluded that prehistoric people drove many of those species to extinction through over-hunting. In their Pleistocene overkill hypothesis, they cite what seems to be a remarkable coincid

18、ence between the arrival of prehistoric peoples in North and South America and the time during which mammoths,(10) giant ground sloths, the giant bison, and numerous other large mammals became extinct. Perhaps the human species was driving others to extinction long before the dawn of history. Hunter

19、-gatherers may have contributed to Pleistocene extinctions in more indirect ways. Besides over-hunting, at least three other kinds of effects have been suggested: direct competition, imbalances between competing species of game animals, and early(15) agricultural practices. Direct competition may ha

20、ve brought about the demise of large carnivores such as the saber-toothed cats. These animals simply may have been unable to compete with the increasingly sophisticated hunting skills of Pleistocene people. Human hunters could have caused imbalances among game animals, leading to the extinctions of

21、species less able to compete. When other predators such as the gray wolf(20) prey upon large mammals, they generally take high proportions of each year s crop of young. Some human hunters, in contrast, tend to take the various age-groups of large animals in proportion to their actual occurrence. If

22、such hunters first competed with the larger predators and then replaced them. they may have allowed more young to survive each year, gradually increasing the populations of favored species As these populations expanded,(25) they in turn may have competed with other game species for the same environm

23、ental niche, forcing the less hunted species into extinction. This theory, suggests that human hunters played an indirect role in Pleistocene extinctions by hunting one species more than another.Which of the following is mentioned as supporting the Pleistocene overkill hypothesisAMany of the animals

24、 that became extinct were quite large.BHumans migrated into certain regions around the time that major extinctions occurred.CThere is evidence that new species were arriving in areas inhabited by humans.DHumans began to keep and care for certain animals. 4.Many ants forage across the countryside in

25、large numbers and undertake mass migrations; these activities proceed because one ant lays a trail on the ground for the others to follow. As a worker ant returns home after finding a source of food, it marks the route by intermittently touching its stinger to the ground and depositing a tiny amount

26、 of trail(5)pheromonea mixture of chemicals that delivers diverse messages as the context changes. These trails incorporate no directional information and may be followed by other ants in either direction. Unlike some other messages, such as the one arising from a dead ant, a food trail has to be ke

27、pt secret from members of other species. It is not surprising then that ant species use(10)a wide variety of compounds as trail pheromones. Ants can be extremely sensitive to these signals. Investigators working with the trail pheromone of the leafcutter ant Atta texana calculated that one milligram

28、 of this substance would suffice to lead a column of ants three times around Earth. The vapor of the evaporating pheromone over the trail guides an ant along the way, (15)and the ant detects this signal with receptors in its antennae. A trail pheromone will evaporate to furnish the highest concentra

29、tion of vapor right over the trail, in what is called a vapor space. In following the trail, the ant moves to the right and left, oscillating from side to side across the line of the trail itself, bringing first one and then the other antenna into the vapor space. As the ant moves to the right, its

30、left antenna arrives in the vapor space. (20)The signal it receives causes it to swing to the left, and the ant then pursues this new course until its right antenna reaches the vapor space. It then swings back to the right, and so weaves back and forth down the trail.According to the passage, why do

31、 ants use different compounds as trail pheromonesATo reduce their sensitivity to some chemicalsBTo attract different types of antsCTo protect their trail from other speciesDTo indicate how far away the food is 5. Many prehistoric people subsisted as hunters and gatherers. Undoubtedly, game animals,

32、including some very large species, provided major components of human diets. An important controversy centering on the question of human effects on prehistoric wildlife concerns the sudden disappearance of so many species of large animals at or near the end(5) of the Pleistocene epoch. Most paleonto

33、logists suspect that abrupt changes in climate led to the mass extinctions. Others, however, have concluded that prehistoric people drove many of those species to extinction through over-hunting. In their Pleistocene overkill hypothesis, they cite what seems to be a remarkable coincidence between th

34、e arrival of prehistoric peoples in North and South America and the time during which mammoths,(10) giant ground sloths, the giant bison, and numerous other large mammals became extinct. Perhaps the human species was driving others to extinction long before the dawn of history. Hunter-gatherers may

35、have contributed to Pleistocene extinctions in more indirect ways. Besides over-hunting, at least three other kinds of effects have been suggested: direct competition, imbalances between competing species of game animals, and early(15) agricultural practices. Direct competition may have brought abou

36、t the demise of large carnivores such as the saber-toothed cats. These animals simply may have been unable to compete with the increasingly sophisticated hunting skills of Pleistocene people. Human hunters could have caused imbalances among game animals, leading to the extinctions of species less ab

37、le to compete. When other predators such as the gray wolf(20) prey upon large mammals, they generally take high proportions of each year s crop of young. Some human hunters, in contrast, tend to take the various age-groups of large animals in proportion to their actual occurrence. If such hunters fi

38、rst competed with the larger predators and then replaced them. they may have allowed more young to survive each year, gradually increasing the populations of favored species As these populations expanded,(25) they in turn may have competed with other game species for the same environmental niche, fo

39、rcing the less hunted species into extinction. This theory, suggests that human hunters played an indirect role in Pleistocene extinctions by hunting one species more than another.The word Besides in line 13 is closest in meaning toAcaused byBwhereasCin addition toDin favor of 6. Because the low lat

40、itudes of the Earth, the areas near the equator, receive more heat Than the latitudes near the poles, and because the nature of heat is to expand and move, Heat is transported from the tropics to the middle and high latitudes. Some of this heat is Moved by winds and some by ocean currents, and some

41、gets stored in the atmosphere in(5) the form of latent heat. The term latent heat refers to the energy that has to be used to Convert liquid water to water vapor. We know that if we warm a pan of water on a stove, it will evaporate, or turn into vapor, faster than if it is allowed to sit at room tem

42、perature. We also know that if we hang wet clothes outside in the summertime they will dry faster than in winter, when temperatures are colder. The energy used in both cases to change (10) liquid water to water vapor is supplied by heatsupplied by the stove in the first case and by the Sun in the la

43、tter case. This energy is not lost. It is stored in water vapor in the atmosphere as latent heat. Eventually, the water stored as vapor in the atmosphere will condense to liquid again, and the energy will be released to the atmosphere. In the atmosphere, a large portion of the Suns incoming energy i

44、s used to evaporate (15) Water, primarily in the tropical oceans. Scientists have tried to quantify this proportion of the Suns energy. By analyzing temperature, water vapor, and wind data around the globe, they have estimated the quantity to be about 90 watts per square meter, or nearly 30 percent

45、of the Suns energy. Once this latent heat is stored within the atmosphere, it can be transported, primarily to higher latitudes, by prevailing, large-scale winds. Or it (20) can be transported vertically to higher levels in the atmosphere, where it forms clouds and subsequent storms, which then rele

46、ase the energy back to the atmosphere.According to the passage, most ocean water evaporation occurs especiallyAaround the higher latitudesBin the tropicsCbecause of large-scale windsDbecause of strong ocean currents 7.A survey is a study, generally in the form of an interview or a questionnaire, tha

47、t provides information concerning how people think and act. In the United States, the best-known surveys are the Gallup poll and the Harris poll. As anyone who watches the news during Line campaigns presidential knows, these polls have become an important part of political life in(5) the United States. North Americans are familiar with the many person on the street interviews on local television news shows. While such interviews can be highly entertaining, they are not necessari