2013年全國大學(xué)英語四級考試題型由寫作、聽力理解、閱讀理解和翻譯四個部分組成，其中閱讀理解占的比重最大為35%，為了幫助廣大考生在12月的全國大學(xué)英語四級考試中獲取高分，唯學(xué)網(wǎng)小編特別針對閱讀理解搜集不少例題及專家解析，希望對考生們有所幫助。

Even plants can run a fever, especially when they're under attack by insects or disease. But unlike humans, plants can have their temperature taken from 3,000 feet away-straight up. A decade ago, adapting the infrared (紅外線) scanning technology developed for military purposes and other satellites, physicist Stephen Paley came up with a quick way to take the temperature of crops to determine which ones are under stress. The goal was to let farmers precisely target pesticide(殺蟲劑) spraying rather than rain poison on a whole field, which invariably includes plants that don't have pest(害蟲) problems.

Even better, Paley's Remote Scanning Services Company could detect crop problems before they became visible to the eye. Mounted on a plane flown at 3,000 feet at night ,an infrared scanner measured the heat emitted by crops. The data were transformed into a color-coded map showing where plants were running "fevers".Farmers could then spot-spray, using 50 to 70 percent less pesticide than they otherwise would.

The bad news is that Paley's company closed down in 1984, after only three years. Farmers resisted the new technology and long-term backers were hard to find.But with the renewed concern about pesticides on produce, and refinements in infrared scanning, Paley hopes to get back into operation.Agriculture experts have no doubt the technology works. "This technique can be used on 75 percent of agricultural land in the United States, "says George Oerther of Texas A&M. Ray Jackson, who recently retired from the Department of Agriculture, thinks.remote infrared crop scanning could be adopted by the end of the decade. But only if Paley finds the financial backing which he failed to obtain 10 years ago.

這是一篇說明文。文章一開頭就介紹了原用于軍事和衛(wèi)星的紅外線掃描技術(shù)，如今被用在農(nóng)業(yè)上。通過遠距離測量植物的溫度來判斷農(nóng)作物是否遭受蟲害和疾病。在第二段中指出，物理學(xué)家帕里組建了帕里遠紅外掃描服務(wù)公司，來專門探測農(nóng)業(yè)方面的情況。最后他的公司在三年后被迫關(guān)閉，主要是因為缺乏資金。另外，農(nóng)民們也一時不能接受這種新技術(shù)。作者期待將來有一天可以解決財政困難，將這一新技術(shù)重新用到農(nóng)業(yè)上去。

26. Plants will emit an increased amount of heat when they are _______

A) sprayed with pesticides B) facing an infrared scanner

C) in poor physical condition D) exposed to excessive sun rays

[答案及分析]：[C]。詞組理解題。本文第一段的第一句話談到：“Even plants can run fever...by insects or disease.”這就告訴了我們植物升高溫度的原因。本句所問的也正是這個原因。因此，C正告訴了我們這一點，所以C是正確答案。

27. In order to apply pesticide spraying precisely, we can use infrared scanning to

_______.

A) estimate the damage to the crops

B) measure the size of the affected area

C) draw a color-coded map

D) locate the problem area

[答案及分析]：[D]詞匯理解題。在第一段的原文中“The goal was to let farmers precisely target pesticide spraying...”其中的意思是“確定”(蟲害發(fā)生的地方)”而答案D是說“要確定問題所在地區(qū)”，信息與本文相符，故D為正確答案;而A、B、C都與本文不符。

28. Farmers can save a considerable amount of pesticide by _______.

A) resorting to spot-spraying B) consulting infrared scanning experts

C) transforming poisoned rain D) detecting crop problems at an early stage

[答案及分析]：[A]。判斷題。問農(nóng)民通過何種方式可節(jié)省殺蟲劑。在文章的第二段中談到帕里遠紅外線掃描服務(wù)公司利用飛機上的遠紅外線掃描儀夜間在3000英尺的高度探測到莊稼的情況，然后可將這些情況提供給農(nóng)民，農(nóng)民可噴灑農(nóng)藥，這樣只使用原來農(nóng)藥量的50%-70%就足夠了。故答案A的信息與本文相符;而B、C、D均不正確。

29. The application of infrared scanning technology to agriculture met with some

difficulties _______.

A) the lack of official support B) its high cost C) the lack of financial D) its failure to help increase production

[答案及分析]：[C]。詞匯理解題。問遠紅外掃描技術(shù)用于農(nóng)業(yè)上時遇到的阻力，原因何在。在本文最后段中指出：1984年，帕里公司被迫關(guān)閉的原因一資金缺乏。并呼吁說：“But only if Paley finds the financial backing which he failed to obtain 10years ago.”其中financial backing的意思與本題C的“financial support”相同。所以答案C正確。

唯學(xué)網(wǎng)小編提醒：關(guān)于全國大學(xué)英語四級考試報名，大學(xué)英語四級考試模擬試題、大學(xué)英語四級考試成績查詢等相關(guān)考試資訊敬請繼續(xù)關(guān)注唯學(xué)網(wǎng)的英語培訓(xùn)欄目。小編認為，考生能夠通過自己的努力最后高分通過全國大學(xué)英語四級考試，對于考生而言，不僅是一個學(xué)習(xí)的經(jīng)過，更是一種自我的挑戰(zhàn)，英語培訓(xùn)欄目小編將為考生全程助戰(zhàn)！