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三級

公共英語三級閱讀文章《動物的羅盤》

時間:2025-06-06 04:52:55 三級 我要投稿
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公共英語三級閱讀文章《動物的羅盤》

  公共英語三級的難度不是很大,但是閱讀理解的難度對于不少考生來說還是不小的。因此,考生一定要加以練習。下面,送給大家一篇公共英語三級閱讀文章。

公共英語三級閱讀文章《動物的羅盤》

  Researchers have found that migrating animals use a variety of inner compasses to help them navigate. Some steer by the position of the Sun. Others navigate by the stars. Some use the Sun as their guide during the day and then switch to star navigation by night. One study shows that the homing pigeon uses the Earth's magnetic fields as a guide in finding its way home and there are indications that various other animals from insects to mollusks, can also make use of magnetic compasses. It is of course very useful for a migrating bird to be able to switch to a magnetic compass when clouds cover the Sun; otherwise it would just have to land and wait for the Sun to come out again.

  Even with the Sun or stars to steer by, the problems of navigation are more complicated than they might seem at first. For example, a worker honeybee that has found a rich source of nectar and pollen flies rapidly home to the hive to report. A naturalist has discovered that the bee scout delivers her report through a complicated dance in the hive, in which she tells the other workers not only how far away the food is, but also what direction to fly in relation to the Sun. But the Sun does not stay in one place all day. As the workers start out to gather the food, the Sun may already have changed its position in the sky somewhat. In later trips during the day, the Sun will seem to move farther and farther toward the west. Yet the worker bees seem to have no trouble at all in finding the food source. Their inner clocks tell them just where the Sun will be and they change their course correspondingly.

  研究人員已經發(fā)現遷徙性動物可以借助各種各樣的體內羅盤來校正方向。有些動物借助太陽的位置辨別方向,有些則依靠星星。還有的白天利用太陽,晚上利用星星。有研究發(fā)現信鴿以地磁場為向導來找到回家的路。還有跡象表明許許多多其它生物,從昆蟲到軟體動物,也能利用這種磁場羅盤。具有這種磁場羅盤,對候鳥來說當然非常有用,因為如果烏云遮日,它可以以磁場為向導繼續(xù)飛行,否則它就只好著陸,等待太陽重新出現。

  即使是借助太陽或星星導航,其中的學問也比它表面看起來的要復雜得多。例如,一只工蜂找到了花圃蜜園,急忙飛回蜂房報信。博物學家發(fā)現這只蜂探在蜂房里跳了一段極為復雜的舞,通過這段舞她不但告訴其它工蜂食物有多遠,而且報告了以太陽為參照的飛行路線。但太陽不會呆在天上不動。當蜂群出發(fā)采食時,太陽可能已經多少改變了它在天空中的位置。出發(fā)得越遲,太陽就越偏西,可這似乎沒給尋找食物源的工蜂們帶來任何不便。它們體內的時鐘告訴他們太陽應在的位置,據此它們相應地改變前進的方向。

  附:公共英語三級閱讀技巧

  (1) 做詞匯問題應注意以下3點:

 、 一個單詞可有不同的意思,而選項常用與上下文語境不符的詞義來迷惑考生。

 、 選項中有時會出現文章中的一個詞或短語,由于這個詞或短語與所考詞匯相近,有可能被當做所考詞匯的定義。

 、 還有一些選項由于拼寫與所考詞匯相似,易迷惑考生。

  (2) 回答主題類問題時可采用略讀法,先讀首段、末段及每個段落的第一個句子。對于這類問題應注意把握全文的內容,而不應以某個段落為依據做出選擇。選好答案后應看看它是否與文章中的每一段落都有聯系。若該選項與文中某一段落毫不相干,便表明選項不正確。

  (3) 回答有關文章細節(jié)的問題時可采取查讀法。在查讀的同時,要默默地重復所尋找的細節(jié)。這種重復可加強視覺感知效果,更快捷、有效地找到所尋求的信息。

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