单选题
第三篇 Unpredictable Earthquake

Humans are forever forgetting that they can"t control nature. Exactly 20 years ago, a Time magazine cover story announced that "scientists are on the verge of being able to predict the time, place and even the size of earthquakes." The people of quake-ravaged (被地震破坏的) Kobe learned last week how wrong that assertion was.
None of the methods conceived two decades ago has yet to discover a uniform wanting signal that preceded all quakes, let alone any sign that would tell whether the coming temblor (地震) is mild or a killer. Earthquake formation can be triggered by many factors, says Hiroo Kanamori, a seismologist (地震学家) at the California Institute of Technology. So, finding one all-purpose warning sign is impossible. One reason: Quakes tart deep in the earth, so scientists can"t study them directly. If a quake precursor were found, it would still be impossible to ward humans in advance of all dangerous quakes. Places like Japan and California are riddle with hundreds, if not thousands, of minor faults.
Prediction would be less important if scientists could easily build structures to withstand tremors. While seismic engineering has improved dramatically in the past 10 to 15 years, every new quake reveals unexpected weakness in "quake-resistant" structures, says Terry Tullis, a geophysicist at Brown University. In Kobe, for example, a highway that opened only last year was damaged. In the Northridge earthquake, on the other hand, well-built structures generally did not collapse.
A recent report in Science adds yet more anxiety about life on the faulty lines. Researchers Fan computer simulations to see how quake resistant buildings would fall in a moderate size temblor, taking into account that much of a quake"s energy travels in a large "pulse" of focused shaking. The results: both steel-frame buildings and buildings that sit on insulating rubber pads suffered severe damage.
More research will help experts design stronger structures and possibly find quake precursors. But it is still a certainty that the next earthquake will prove once again that every fault cannot be monitored and every highway cannot be completely quake-proofed.
单选题 From the first paragraph, it can be safely inferred that ______.
【正确答案】 B
【答案解析】[解析] 根据第一段和第二段,人们无法预测所有的地震,更无法达到对地震的等级预测到准确无误的程度。所以说人们夸大了其预测地震的能力。
单选题 One of the main difficulties in accurate earthquake forecasting is that ______.
【正确答案】 D
【答案解析】[解析] 根据第二段第三行,地震的成因是由多种因素决定的,其中之一是地震从地球深层开始形成,科学家们根本无法直接研究它们。
单选题 What does the word precursor in the context in the second paragraph mean?
【正确答案】 C
【答案解析】[解析] precursor这个词的前缀是pre-“前面的,提前的”,根据上下文,这个词的意思是指在地震发生之前可以预测到地震发生的情况。
单选题 What does the author mean when he mentions the damage caused by earth quakes?
【正确答案】 C
【答案解析】[解析] 地震难以预测,地震对建筑物的损坏程度也难以预测。
单选题 According to the passage all the following statements are TRUE except ______.
【正确答案】 C
【答案解析】[解析] 文章最后一段指出,更多的研究将有助于专家们设计更耐震的结构,甚至可能发现可预测地震的线索。但有一点可以肯定,地震无法完全预测,不是所有的高速公路都完全防震。