Three “Great Walls” built around the United States’ Tornado Alley could reduce tornadoes f

Three “Great Walls” built around the United States’ Tornado Alley could reduce tornadoes from destroying billions of dollars in property and endangering millions of lives, a physicist has claimed.
Professor Rongjia Tao of Temple University, Philadelphia unveiled a proposal this week calling for the construction of three 1,000-foot barriers up to 100 miles long, which would act like hill ranges and soften winds before tornadoes could form, the BBC reports.
The $16.9 billion plan would call for the faux hill ranges in North Dakota, along the border between Kansas and Oklahoma, and in Texas and Louisiana, ostensibly saving billions of dollars in damage every year, Tao said. The walls would not shelter towns, he said, but instead would soften the streams of hot southern and cold northern air that form tornadoes when they clash in the first place.
But critics laughed at Tao’s proposals. Leading tornado experts pointed to areas that are already protected by hill ranges the size of the barriers Tao is proposing, yet still have plenty of tornados, like parts of Oklahoma, Arkansas and Missouri. And even if the plan did work, it would create more problems than it would solve, scientists said, by creating catastrophic weather side effects.
“Everybody I know is of 100% agreement – this is a poorly conceived idea,” Professor Joshua Wurman of the Center for Severe Weather Research. “From what I can gather his concept of how tornadoes form is fundamentally flawed（有缺陷的）. Meteorologists（气象学家） cringe（尴尬） when they hear about ‘clashing（交锋） hot and cold air’. It’s a lot more complicated than that.”
【小题1】What does the underlined word “unveiled”mean in the fourth paragraph？A．remindedB．came up withC．referredD．applied【小题2】What’s the main idea of the passage?A．The different opinions on the proposal that the walls will reduce the loss caused by tornadoes.B．How to solve the problems that are caused by tornadoes.C．The proposal mentioned in the paragragh is totally wrong.D．The proposal to reduce tornadoes is effective.【小题3】 From the passage, we can infer that .A．the tornadoes form by clashing（交锋） hot and cold air.B．if the walls are built, they will work well.C．if the plan is carried out, we will have more problems than expected.D．The walls not only soften the winds but also shelter the towns.【小题4】Which of following statements is true according to the passage？A．Leading tornado experts think that would soften the streams of hot southern and cold northern air that form tornadoes.B．Professor Joshua Wurman pointed out that the plan will be expensive.C．Professor Rongjia Tao is against the construction of walls to prevent the tornadoes.D．the plan will not be carried out because it will creating serious weather side effects.　

(答案→)　 解析：本文是一篇报道。文章讲述了美国专家对Professor Rongjia Tao提出的“建高墙”阻止龙卷风计划的不同意见。【小题1】考查猜测词义。根据文章第一段中的Professor Rongjia Tao unveiled a proposal this week calling for the construction of three 1,000-foot barriers up to 100 miles long可知，这里是提出的意思。【小题2】考查主旨要义。根据这段话的内容可知，专家对建高墙防止龙卷风的发表的不同意见。故选A。【小题3】考查推理判断。根据文章第四段中的And even if the plan did work, it would create more problems than it would solve, scientists said, by creating catastrophic weather side effects.可知，即使高墙起作用，它会产生无法解决的恶劣气候的副作用。故选C。【小题4】考查细节理解。根据文章中对这个建议的不同意见可知，这个计划实施的可能性不大。故选D。

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