考前冲刺:2021年考研英语阅读经典试题及答案(十八)
发布时间:2020-10-10
英语是考研初试当中比较拉分的科目,历来令不少考生又爱又恨。许多考生的英语都有很大的进步空间,因此英语该如何学就成为了众多考生关心的重点。想要学习英语,实战经验很重要。下面,51题库考试学习网为大家带来考研初试英语科目的一些模拟试题,正在备考的小伙伴赶紧练起来吧。
Although recent years have seen substantial
reductions in noxious pollutants from individual motor vehicles, the number of
such vehicles has been steadily increasing. Consequently, more than 100 cities
in the United States still have levels of carbon monoxide, particulate matter,
and ozone (generated by photochemical reactions with hydrocarbons from vehicle
exhaust) that exceed legally established limits. There is a growing realization
that the only effective way to achieve further reductions in vehicle emissions — short of a massive shift away from the
private automobile — is to
replace conventional diesel fuel and gasoline with cleaner-burning fuels such
as compressed natural gas, liquefied petroleum gas, ethanol, or methanol.
All of these alternatives are carbon-based
fuels whose molecules are smaller and simpler than those of gasoline. These
molecules burn more cleanly than gasoline, in part because they have fewer, if
any, carbon-carbon bonds and the hydrocarbons they do emit are less likely to
generate ozone. The combustion of larger molecules, which have multiple
carbon-carbon bonds involves a more complex series of reactions. These
reactions increase the probability of incomplete combustion and are more likely
to release uncombusted and photochemically active hydrocarbon compounds into
the atmosphere. On the other hand, alternative fuels do have drawbacks.
Compressed natural gas would require that vehicles have set of heavy fuel tanks — a serious
liability in terms of performance and fuel efficiency — and liquefied petroleum gas faces
fundamental limits on supply.
Ethanol and methanol, on the other hand,
have important advantages over other carbon-based alternative fuels: they have
higher energy content per volume and would require minimal changes in the
existing network for distributing motor fuel. Ethanol is commonly used as a
gasoline supplement, but it is currently about twice as expensive as methanol,
the low cost of which is one of its attractive features. Methanol’s most attractive feature, however, is
that it can reduce by about 90 percent the vehicle emissions that form ozone,
the most serious urban air pollutant.
Like any alternative fuel, methanol has its
critics. Yet much of the criticism is based on the use of “gasoline clone” vehicles that do not incorporate even
the simplest design improvements that are made possible with the use of
methanol. It is true, for example, that a given volume of methanol provides
only about one-half of the energy that gasoline and diesel fuel do; other
things being equal, the fuel tank would have to be somewhat larger and heavier.
However, since methanol-fueled vehicles could be designed to be much more
efficient than “gasoline clone” vehicles fueled with methanol they would
need comparatively less fuel. Vehicles incorporating only the simplest of the
engine improvements that methanol makes feasible would still contribute to an
immediate lessening of urban air pollution.
1. The author of the text is primarily
concerned with
[A] countering a flawed argument that
dismisses a possible solution to a problem.
[B] reconciling contradictory points of
view about the nature of a problem.
[C] identifying the strengths of possible
solutions to a problem.
[D] discussing a problem and arguing in
favor of one solution to it.
2. According to the text, incomplete
combustion is more likely to occur with gasoline than with an alternative fuel
because
[A] the combustion of gasoline releases
photochemically active hydrocarbons.
[B] the combustion of gasoline embraces an
intricate set of reactions.
[C] gasoline molecules have a simple
molecular structure.
[D] gasoline is composed of small
molecules.
3. The text suggests which of the following
about air pollution?
[A] Further attempts to reduce emissions
from gasoline-fueled vehicles will not help lower urban air-pollution levels.
[B] Attempts to reduce the pollutants that
an individual gasoline-fueled vehicle emits have been largely unsuccessful.
[C] Few serious attempts have been made to
reduce the amount of pollutants emitted by gasoline-fueled vehicles.
[D] Pollutants emitted by gasoline-fueled
vehicles are not the most critical source of urban air pollution.
4. Which of the following most closely
parallels the situation described in the first sentence of the text?
[A] Although a town reduces its public
services in order to avoid a tax increase, the town’s tax rate exceeds that of other towns in
the surrounding area.
[B] Although a state passes strict laws to
limit the type of toxic material that can be disposed of in public landfills,
illegal dumping continues to increase.
[C] Although a town’s citizens reduce their individual use of
water, the town’s water supplies
continue to dwindle because of a steady increase in the total populating of the
town.
[D] Although a country attempts to increase
the sale of domestic goods by adding a tax to the price of imported goods, the
sale of imported goods within the country continues to increase.
5. It can be inferred that the author of
the text most likely regards the criticism of methanol as
[A] flawed because of the assumptions on
which it is based.
[B] inapplicable because of an
inconsistency in the critics’ arguments.
[C] misguided because of its exclusively
technological focus.
[D] inaccurate because it ignores consumers’ concerns.
参考答案及解析
1.【答案】C
【考点解析】这是一道中心主旨题。本文的中心主旨句是首段的尾句。通过对首段尾句以及其它段落主题句的阅读和理解,可以推导出本题的正确选项是C。考生在破解此类题型时一定要首先抓住原文的中心主旨句以及各段的主题句。
2.【答案】B
【考点解析】本题是一道指代词题型。根据题干中的“incomplete combustion”可将本题的答案信息来源迅速确定在第二段的第四句,该句中的指代词“these”暗示本题的具体答案信息来源应该在第二段的第三句。通过阅读和理解第二段的第三句可推导出本题的正确选项是B。考生在解题时对指代词一定要认真理解。
3.【答案】A
【考点解析】本题是一道审题定位题型。通过题干中的“air pollution”可将本题的答案信息来源迅速确定在第一段,因为第一段首句中含有“noxious pollutants”,都在谈污染的问题。通过阅读和理解第一段,尤其是第一段尾句即全文的中心主旨句,可推导出本题的正确选项是A。这是一道比较难的题。考生在解题时一定要具备审题定位能力,还要具备归纳和推导能力。
4.【答案】C
【考点解析】这是一道类比题型,因为本题题干中含有“parallels”(与……相当,与……一样)一词。本题题干已将类比的参照对象确定在第一段的首句。通过仔细阅读和理解第一段的首句,可推导出本题的正确选项是C,因为该选项涉及的增减关系的前提条件和原文一脉相承。考生在破解这种题型时应对原文所表达的内容与关系有明确的认识和把握,不可以无根据地推导。
5.【答案】A
【考点解析】这是一道细节推导题型。本题题干中的“the criticism of methanol”把本题的答案信息来源确定在第四段的第一、二句。通过阅读和理解这两句话,尤其是第二句话,就可推导出本题的正确选项A。考生在破解本题时一定要注意第二句话的第一个词“Yet”在语意上所起的作用。考生在解题时一定要重视启承转合词的出现和功能。
以上就是51题库考试学习网为大家带来的全部内容,希望能给大家一些帮助。51题库考试学习网提醒:在最后阶段,调整自己的心态也是非常重要的,每年都有考生临考前放弃,所以小伙伴们要注意不要给自己太大的压力哦。另外,小伙伴们如果还有其他关于考研信息的疑问,也可以留言咨询哦。
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