公共英语四级辅导：PETS4阅读精讲（53）

会计考友 · 发表于 2012-8-14 13:19:23

　　Reading Comprehension
　　part A
　　Read the following two texts. Answer the questions below each text by choosing A.B.C or D. When was helium in the University formed?
　　The elements other than hydrogen and helium exist in such small quantities that it is accurate to say that the universe is somewhat more than 75 percent hydrogen.
　　Astronomers have measured the abundance of helium throughout our galaxy and in other galaxies as well. Helium has been found in old stars, in relatively young ones, in interstellar gas, and in the distant objects known as quasars. Helium nuclei have also been found to be constituents of cosmic rays that fall on the earth (cosmic “rays” are not really a form of radiation; they consist of rapidly moving particles of numerous different kinds). It doesn’t seem to make very much difference where the helium is found. Its relative abundance never seems to vary much. In some places, there may be slightly more of it; in others, slightly less, but the ratio of helium to hydrogen nuclei always remains about the same.
　　Helium is created in stars. In fact, nuclear reactions that convert hydrogen to helium are responsible for most of the energy that stars produce. However, the amount of helium that could have been produced in this manner can be calculated, and it turns out to be no more than a few percent. The universe has not existed long enough for this figure to be significantly greater. Consequently, if the universe is somewhat more than 25 percent helium now, then it must have been about 25 percent helium at a time near the beginning.
　　However, when the universe was less than one minute old, no helium could have existed. Calculations indicate that before this time temperatures were too high and particles of mater were moving around much too rapidly. It was only after the one-minute point that helium could exist. By this time, the universe had cooled sufficiently that neutrons and protons could stick together. But the nuclear reactions that led to the formation of helium went on for only a relatively short time. By the time the universe was a few minutes old, helium production had effectively ceased.
　　1.What does the passage mainly explain?
　　A.How stars produce energy.
　　B.The difference between helium and hydrogen.
　　C.When most of the helium in the universe hydrogen.
　　D.Why hydrogen is abundant.
　　2.According to the passage, helium is ____.
　　A.the second-most abundant element in the universe
　　B.difficult to detect
　　C.the oldest element in the universe
　　D.the most prevalent element in quasars
　　3.Why does the author mention “cosmic rays” in paragraph 2?
　　A.as part of a list of things containing helium.
　　B.As an example of an unsolved astronomical puzzle.
　　C.To explain how the universe began.
　　D.To explain the abundance of hydrogen in the universe.
　　4.The creation of helium within stars ____.
　　A.cannot be measured
　　B.produces energy
　　C.produces helium to be much more abundant in old stars than in young stars.
　　5.Most of the helium in the universe was formed _____.
　　A.in interstellar space
　　B.in a very short time
　　C.during the first minute of the universe’s existence
　　D.before most of the hydrogen

会计考友 · 发表于 2012-8-14 13:19:24

</p>　　解析：
　　1.C
　　本文的题目是When was helium in the University formed?根据题目并结合文章的内容，我们可以判断，本文主要介绍的是氦元素是何时在宇宙中形成的。
　　2.A
　　在第一段中我们知道：宇宙中除了氢和氦的数量比较多之外，其它元素的数量都很少。而且，氢在宇宙元素总量中占75%，所以氦元素在宇宙中一定是占第二位，仅次于氦。
　　3.A
　　文章第二段中介绍了许多包含氦的物质，包括in old stars, in relatively young ones, in interstellar gas, and in the distant objects known as quasars同时作者还提到了宇宙射线，并告诉我们宇宙射线中也包含氦。因此，作者在这里也提到了cosmic rays的目的是要使人们知道另外一种包含氦的物质，具体而言，就是说宇宙射线也是众多包含氦元素的物质中的一部分。
　　4.B
　　第三段开头有这样一句话：In fact, nuclear reactions that convert hydrogen to helium are responsible for most of the energy that stars produce. 这句话的意思是，星体产生的多数能量来源与巴氢转变为氦的原子核反应。也就是说，星体上的氢转变为氦的原子核反应产生了能量，这与选项A中的“星体中的氦的创造过程中产生了能量”是一致的。中华考试网
　　5.B
　　文章的末尾有这样一句话：But the nuclear reactions that led to the formation of helium went on for only a relatively short time. 这句话的意思是，但是由于导致氦形成的原子核反应持续的时间相对较短。文章在最后指出，在宇宙形成的早期，氦并不存在，因为那时的温度太高。后来随着温度逐渐降低，中子和质子才得以粘在一起。原子核反应形成了氦，但这一过程进行的时间很短。到了the universe was a few minutes old的时候，氦的生产就停止了。

　　Y2K
　　The sudden emergence of Y2K in headlines around the world is no algebraic code, nor mysterious symbol of doom. It is, very simply, shortened for the coming transition to the year 2000 in the western calendar and the problems that might and/or are likely to occur as a result of the data change. Virtually all computers and automated systems were formulated using the solar-based calendar, as opposed to the Chinese lunar calendar or other eastern calendars.
　　Computers and automated systems around the world have only been using two digits in the year field in the computer code that tells the computer or automated system what to do. When there is a four-digit change in the calendar at mid-might on December 31, 1999, many computers and automated systems may malfunction unless the year field is fixed. The thinking the year is 1900. this could cause a lot of problems if electrical power grids(电极), water systems, energy supply systems, medical devices, shipping ports and airports fail or have to be closed.
　　No one knows what is going to happen, but no one is immune
　　No one really knows what is going to happen down to the last detail when the clock strikes the mid-night around the world on January 1,2000. the situation changes daily as more and more people learn about the problem and work hard to do something about it. The world had never experienced a millennium change with automated system and computers.
　　The effects will be serious if action is not taken
　　We do know this year 200 date change is serious and no family, business, community or country is immune to the Y2K problems. Virtually everyone will see some type of disruption-only the scope and impact are in question. Some, in countries where much Y2K repair work has already been done, may only see a harmless service warning light come on in their cars. others in more remote or less developed areas could be without food, water, telecommunications and/or electricity for hours, days, weeks or months. It is in everyone’s interest, around the world, to avoid serious long-term disruption that could affect the global economy and strain humanitarian efforts. But Y2K knows no national or political boundaries.
　　The problem is bigger than most people around the world think it is. Most people don’t sit around thinking about or where their electricity, water and other basic supplies come from. Most people don’t really think about how telephones, medical equipment or home appliances work. Microchips are embedded in just about every automated device or system we use today. Not all will be affected by Y2K, but many will and it is important to know which devices and systems are vulnerable, fix the problem and test it again and again to make sure it will work.
　　We see that computers and automated systems can do so much, and come to rely on them for the most basic services. Most of us have probably never thought about how a computer can not think on its own like a human and what that means. Many computers and automated systems are programmed to only recognize 99 years. Unless these Y2K problems are repaired, some systems will malfunction because the computer is not intelligent enough to know what year “00” stands for. Those computers and systems have to be told not to shut down, but keep working onto 2000.
　　6.According to the passage, which of the following statement is true?
　　A.The Y2K problem is so serious that it means the end of the world.
　　B.The Y2K problem is just as simple as an algebraic code.
　　C.The Y2K problem is a likely occurrence as a result of the date change.
　　D.The Y2K problem is nothing to worry about.
　　7.The reason for the Y2K problem to happen is that____.
　　A.computer and automated system can only read two digit in the year field
　　B.computers and automated systems do not recognize four digits in the year field
　　C.the year field is fixed, so computers and automated systems will be out of order
　　D.all of the above reasons are possible reasons for the Y2K problem to occur
　　8.The sentence “But the Y2K knows no national or political boundaries” means that ____.
　　A.virtually no country can be immune to the Y2K problem
　　B.the Y2K problem does not consider any country as an independent country
　　C.the Y2K problem considers the whole world as one country
　　D.the Y2K problem can not tell national boundaries from political boundaries
　　9.We can infer from the passage that ____.
　　A.Y2K problems will be only damage our computers
　　B.some people may be immune to Y2K problem if their computer are more advanced
　　C.some people in more remote or less developed areas can be less affected by it
　　D. the occurrence of Y2K is not a matter of possibility, but a matter of scope and impact.
　　10. Most people around the world do not take Y2K problem seriously enough because____.
　　A.most people just use electricity, telephones , medical equipment, and home appliances but do not know how they work
　　B.some devices and systems are not vulnerable to Y2K problem
　　C.some people d not rely on computers and automated systems at all
　　D.they believe that the future computer will be more intelligent

会计考友 · 发表于 2012-8-14 13:19:25

</p>　　解析：
　　6.C
　　这道题要求考生从给出的四个选项中选出一个于原文内容相符的选项，所以对各个选项分别考察即可。
　　7.D
　　通过第二段的叙述，计算机和自动系统只能识别年份域中的两位。当年分域中的四位发生了变化时，计算机和自动系统就无法识别了。另一方面，如果为了避免这一问题而使年份域固定不变，计算机和自动系统的时间会固定不变，或停止工作，或者不能正确处理日期。可见A，B，C都是问题发生的原因。
　　8.A
　　此题考察我们对于句子the Y2K knows no national or political boundaries的理解。它的意思是：千年虫问题没有国家和政治的界限。在文章的第三和第四段中，作者指出没有人可以不受千年虫问题的影响，这一问题带给人们的影响无处不在。所以，千年虫问题可以传播于各个国家，没有任何一个国家可以免受千年虫问题的影响。
　　9.D
　　通过文章第四段的叙述，我们可以知道：没有任何一个家庭，社会或个人可以免受千年虫问题的影响，每个人都将看到千年虫问题引发的某些类型的破坏，而只有影响的范围和影响带来的冲击是未知的。可见，千年虫问题的发生并不是可能性的问题，而是范围和影响力的问题。
　　10.A
　　作者在文章的第五段指出：许多人对于千年虫问题还没有给予足够的重视，因为微型芯片被嵌入了我们使用锝大多数自动装置和系统中，这些人实际上并不知道电话机，医疗设备或家用电器是怎样工作的。因此他们还没有意识到其实自己的生活也将受到千年虫问题的影响。考试用书
　　part B Translation
　　11.
　　Here on Earth, daytime is the period when the atmosphere is lighted; sunlight is reflected from water droplets and large molecules in the air. The sky may be dull and gray, deep blue, or have shades of red and many other colors as at sunrise and sunset.
　　12.
　　It’s the same on Mercury, pluto, and the Moon, which also don’t have atmosphere. Even when the area around a Moon explorer is brightly lighted by the sun, the sky above is black.
　　13.
　　We see light reflections-trees, books, future; also light producers only when we look at them directly.
　　14.
　　The Moon’s sky is black, as well as the skies of Mercury and pluto, because there is nothing around them to reflect sunlight. on the Moon you either in intense sunlight, or deepest darkness.
　　15.
　　Astronauts report that the view from space is fantastic. But that is only when they look back at Earth. otherwise the scene is monotonous. Except for the stars, which are intensely bright, the sky is black.
　　解析：
　　11.
　　在地球上，白天太阳照射着大气，阳光被空气中的水滴和大分子反射，这样，在日出或日落时，天空看起来就是暗色的，灰蒙蒙的，或者是深蓝色的，红色的以及各种各样其他的颜
　　12.
　　在水星，冥王星和月球上同样没有大气。即使月球探测器的周围被太阳照得雪亮，上面的天空还是黑色的。
　　13.
　　我们看到的反光体有树木，书本，家具等;而只有我们直视的时候才能看到发光体。
　　14.
　　月球的天空与水星，冥王星一样都是黑色的，因为他们的周围没有反射阳光的物质。在月球上，你要么处在强光照射下，要么处在一片黑暗中。
　　15.
　　据宇航员的报告说，在太空中只有朝着地球才能看到美妙的景色，而其他方向都是单调乏味的;除了发出强光的恒星之外，太空一片漆黑。

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[PETS四级] 公共英语四级辅导：PETS4阅读精讲（53）

公共英语四级辅导：PETS4阅读精讲（53）

公共英语四级辅导：PETS4阅读精讲（53）

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