Read the following passage. Argentavis magnificens, the largest bird to

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问题     Read the following passage.
    Argentavis magnificens, the largest bird to have ever inhabited Earth, lived 6 million years ago in the southern part of South America that roughly corresponds to modern-day Argentina. The bird, which is known only through fossil remains, weighed up to 68 kilograms. There is some debate about whether this bird was able to fly or whether it had lost its ability to fly at some point during its evolution.
    First, there is the problem of lifting off into the air. Based on its skeleton, the bird’s total wingspan was nearly seven meters. Wings this long would have hit the ground if the bird had tried to lift off from a standing position. Modern flying birds have wing-to-body proportions that allow them to take off without hitting the ground with their wings.
    Second, even if the bird had managed to lift off, it does not appear to have had enough muscle strength to make continuous flight possible. As large as it was, the Argentavis does not appear to have had sufficient muscles to keep its huge wings moving. It is highly improbable that its muscles could move its wings fast enough to keep it in the air for extended periods.
    Third, according to the theory of evolution, animals only have abilities that give them an advantage in their struggle to survive. Flying would not have given this giant bird any advantage. It did not need to fly in order to escape predators. Because of its size, it had no predators. It could not fly to hunt because it would have been such a clumsy and inefficient flier that it could not possibly have captured enough food. The bird, therefore, probably lost the ability to fly during its evolution.
    Now listen to part of a lecture on the topic you just read about.
    Summarize the points made in the lecture, being sure to explain how they respond to the specific points made in the reading passage.
Your reading gives reasons to doubt that this giant bird could fly; however, it is quite probable that it did fly. There’s really nothing mysterious about how this bird got off the ground, flew around, and fed itself. First, instead of taking off from a standing position, the bird could have used a running start. It could have stretched out its wings, run down a small hill, and lifted off into the wind. The region where the bird’s fossils were discovered contains many such hills. Also, the bird’s strong thighbones and large feet suggest it could run and this method for getting into the air could explain why it had those characteristics.
    Second, there’s no reason why the bird would’ve had to keep flapping its wings in order to stay in the air. It could ’ve stayed in the air by catching so-called thermals, or warm currents of air that rise up into the atmosphere. Many large birds, such as condors and eagles, use such currents to glide for hours without moving their wings.
    Third, the ability to fly would’ve been very useful for this bird. Why? Because it was probably a scavenger. That is, it fed on animals that were already dead, rather than hunting live animals. Scavengers often need to look for dead animals over a large area, so that they can find sufficient food. And how could Argentavis magnificens scavenge successfully? By flying. That way it could cover the large distances necessary for successful scavenging.

选项

答案     Based on three pieces of evidence, the reading passage surmises that Argentavis magnificens, the largest bird on earth in ancient times, was not capable of flying. Yet the lecturer’s analysis conies to the opposite conclusion.
    Firstly, the reading passage mentions the problem of taking off. The huge wings of Argentavis magnificens would have hit the ground when it flapped its wings to lift off from a standing position. But the lecturer refutes that the bird could have run down a small hill and lifted off, instead of taking a standing position. This possibility is supported by two findings: the bird’s fossils were found in hilly areas and the bird had strong thighbones as well as large feet.
    The reading passage then discusses the bird’s insufficient muscle strength. As suggested in the passage, the bird’s muscles were not enough to support flying for a long time. Yet the lecturer points out another possibility: the bird could take advantage of the thermals to glide without flapping its wings repeatedly, just as condors and eagles do.
    Thirdly, the reading passage argues that the bird probably lost its ability to fly during the evolution as flying was not an advantage for them to survive. Flying to hunt would be too cumbersome and inefficient for a bird of this size. The lecturer doubts this theory, as the bird could have been a scavenger. And flying would allow it to search a large area for sufficient food.

解析     题目:有人喜欢立刻买刚上市的电子产品,而另一些人则选择先等待。你更喜欢哪种做法?为什么?
    本题属于“二选一”的类型,要求考生从“选择立刻买刚上市的电子产品”或“先等待”中择其一。文章开头可以结合一些时事来描述抢购的现象,然后说明自己的选择。因为题目问的是考生的喜好(preference),所以可以着重谈谈自己的选择和原因,也可以直接分析另一个选择的弊端,或者通过分析人们做出另一个选择的深层次原因来揭露这种选择的弊端。在结尾段,不推荐过多重复总结前文已提到的原因,最好能提出一些新观点,这样会让文章显得更加自然,论点更有轻重的层次,避免给考官以累赘之感。
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