是一道句意改写题...There is still no universally agreed-on explanation for why there should be such a dramatic cessation of tree growth at the upper timberline.Various environmental factors may play a role.Too much snow,for example,can smothe

是一道句意改写题...There is still no universally agreed-on explanation for why there should be such a dramatic cessation of tree growth at the upper timberline.Various environmental factors may play a role.Too much snow,for example,can smothe
是一道句意改写题...
There is still no universally agreed-on explanation for why there should be such a dramatic cessation of tree growth at the upper timberline.Various environmental factors may play a role.Too much snow,for example,can smother trees,and avalanches and snow creep can damage or destroy them.Late-lying snow reduces the effective growing season to the point where seedlings cannot establish themselves.【Wind velocity also increases with altitude and may cause serious stress for trees,as is made evident by the deformed shapes at high altitudes.】 Some scientists have proposed that the presence of increasing levels of ultraviolet light with elevation may play a role,while browsing and grazing animals like the ibex may be another contributing factor.Probably the most important environmental factor is temperature,for if the growing season is too short and temperatures are too low,tree shoots and buds cannot mature sufficiently to survive the winter months.
9.Which of the sentences below best express the essential information in the highlighted sentence in the passage?In correct choices change the meaning in important ways or leave out essential information.
① Because of their deformed shapes at high altitudes,trees are not likely to be seriously harmed by the strong winds typical of those altitudes.
② As altitude increases,the velocity of winds increase,leading to a serious decrease in the number of trees found at high altitudes.
③ The deformed shapes of trees at high altitudes show that wind velocity,which increase with altitude,can cause serious hardship for trees.
 ④Increased wind velocity at high altitudes deforms the shapes of trees,and this may cause serious stress for trees.
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帮我分析一下三和四吧,这两个真的想不清楚,我选了3.

是一道句意改写题...There is still no universally agreed-on explanation for why there should be such a dramatic cessation of tree growth at the upper timberline.Various environmental factors may play a role.Too much snow,for example,can smothe
3并没有遗漏重要信息.但是,它改变了原句主语和宾语的位置.原句的主语是Wind velocity ,其中的一个分句宾语是deformed shapes .而3的主语是deformed shapes ,这样也就改变了强调的对象.所以改变了作者原来的意思,也就是change the meaning in important ways .所以在4和3之间,3没有4好,4是精确改写.选择4

什么意思？？？

第四相中的词与原句吻合度最高 而3中把stress换成hardship

虽然是好久以前的问题,不过还是想说..楼上的貌似托福专家不要扯淡好不好 答案就是c啊 太不负责任了.