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2011年雅思阅读模拟试题(1)

发布时间:2013-09-03 15:02:01 来源:杭州朗阁培训中心 编辑:杭州朗阁小编
  在雅思阅读考试中,掌握了雅思阅读长难句的理解和分析的方法对于大家解答雅思阅读考试题目和有非常大的帮助。  在IELTS测试中所有问...

 

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  在雅思阅读考试中,掌握了雅思阅读长难句的理解和分析的方法对于大家解答雅思阅读考试题目和有非常大的帮助。

  在IELTS测试中所有问题的答案只能是一个,除非另有说明。即使在多重选择题中,有不止一个符合答案,也只能选择一个最为合适的作为答案。IELTS测试的所有答案务必要填在所给的"answer sheet"纸上。否则,即使您完成了全部问题,也是没有任何分数,

  在开始阅读所给文章前,应首先弄清需要回答的问题,再带着这些问题,有的放矢地去读那些与答题有关的部分,有些部分则完全不看,这样就可以节省出更多时间,达到事半功倍的效果。如果问句是以图表形式出现,那么图表栏目中,应标有一些文字题目,这些词/短语可用作关键词语。所以在答题时应细读图表中的词/短语,从而清楚地知道是何种问题,如何回答。

  下面,杭州朗阁小编为大家整理了2011年的雅思阅读考试模拟试题,大家可以参考一下。

  Sun's fickle heart may leave us cold 25 January 2007 From New Scientist Print Edition. Stuart Clark

  1   There's a dimmer switch inside the sun that causes its brightness to rise and fall on timescales of around 100,000 years - exactly the same period as between ice ages on Earth. So says a physicist who has created a computer model of our star's core.

 

  2   Robert Ehrlich of George Mason University in Fairfax, Virginia, modelled the effect of temperature fluctuations in the sun's interior. According to the standard view, the temperature of the sun's core is held constant by the opposing pressures of gravity and nuclear fusion. However, Ehrlich believed that slight variations should be possible.

  3   He took as his starting point the work of Attila Grandpierre of the Konkoly Observatory of the Hungarian Academy of Sciences. In 2005, Grandpierre and a collaborator, Gábor ágoston, calculated that magnetic fields in the sun's core could produce small instabilities in the solar plasma. These instabilities would induce localised oscillations in temperature.

  4   Ehrlich's model shows that whilst most of these oscillations cancel each other out, some reinforce one another and become long-lived temperature variations. The favoured frequencies allow the sun's core temperature to oscillate around its average temperature of 13.6 million kelvin in cycles lasting either 100,000 or 41,000 years. Ehrlich says that random interactions within the sun's magnetic field could flip the fluctuations from one cycle length to the other.

  5   These two timescales are instantly recognisable to anyone familiar with Earth's ice ages: for the past million years, ice ages have occurred roughly every 100,000 years. Before that, they occurred roughly every 41,000 years.

  6   Most scientists believe that the ice ages are the result of subtle changes in Earth's orbit, known as the Milankovitch cycles. One such cycle describes the way Earth's orbit gradually changes shape from a circle to a slight ellipse and back again roughly every 100,000 years. The theory says this alters the amount of solar radiation that Earth receives, triggering the ice ages. However, a persistent problem with this theory has been its inability to explain why the ice ages changed frequency a million years ago.

  7   "In Milankovitch, there is certainly no good idea why the frequency should change from one to another," says Neil Edwards, a climatologist at the Open University in Milton Keynes, UK. Nor is the transition problem the only one the Milankovitch theory faces. Ehrlich and other critics claim that the temperature variations caused by Milankovitch cycles are simply not big enough to drive ice ages.

  8   However, Edwards believes the small changes in solar heating produced by Milankovitch cycles are then amplified by feedback mechanisms on Earth. For example, if sea ice begins to form because of a slight cooling, carbon dioxide that would otherwise have found its way into the atmosphere as part of the carbon cycle is locked into the ice. That weakens the greenhouse effect and Earth grows even colder.

  9   According to Edwards, there is no lack of such mechanisms. "If you add their effects together, there is more than enough feedback to make Milankovitch work," he says. "The problem now is identifying which mechanisms are at work." This is why scientists like Edwards are not yet ready to give up on the current theory. "Milankovitch cycles give us ice ages roughly when we observe them to happen. We can calculate where we are in the cycle and compare it with observation," he says. "I can't see any way of testing [Ehrlich's] idea to see where we are in the temperature oscillation."

  杭州朗阁最后提醒考生注意,IELTS阅读考试应从在需要回答的问题中寻找关键词语开始,需要回答的问题中总会有些词或短语与文章中的某些词、短语完全相同,或词义相近、或者相关。寻找关键词的顺序如下:

  问句主语中的名词 → 谓语动词(行为动词) → 宾语部分的名词

  上述三个关键词可用作索引,用于在文章中找出答案的所在位置。一些介词短语或惯用表达法也可用作关键词语。特别是粗体字专有名词(表明数字、日期、时间、地点的词)均可用作关键词。

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