托福考试真题及答案

在日常学习中，我们时常需要做些练习题，而与练习题如影随形的.则是答案，借助答案我们可以更好地掌握此类题型的解题思路和方法。以下是小编帮大家整理的托福考试真题及答案，希望可以帮助到有需要的朋友。

Early Ideas about Deep-sea Biology

In 1841 Edward Forbes was offered the chance to serve as naturalist aboard HMS Beacon,an English Royal Navy ship assigned to survey the Aegean Sea.For a year and a half the Beacon crisscrossed the Aegean waters.During that time Forbes was able to drag his small,triangular dredge—a tool with a leather net for capturing creatures along the sea bottom—at a hundred locations,at depths ranging from 6 to 1,380 feet.He collected hundreds of different species of animals,and he saw that they were distributed in eight different depth zones,each containing its own distinct assemblage of animal life,the way zones of elevation on the side of a mountain are populated by distinct sets of plants.

Forbes also thought he saw,as he later told the British Association,that“the number of species and individuals diminishes as we descend,pointing to a zero in the distribution of animal life as yet unvisited.”This zero,Forbes casually speculated—he simply extended a line on his graph of animal number versus depth—probably began at a depth of 1,800 feet.Below that was the final zone in Forbes’s scheme,zone nine,a zone that covered most of the ocean floor and thus most of the solid surface of Earth:Forbes called this the azoic zone,where no animal,to say nothing of plants,could survive.

Forbes’s azoic zone was entirely plausible at the time,and it was certainly far from the strangest idea that was then entertained about the deep sea.In the first decade of the nineteenth century,a French naturalist named François Péron had sailed around the world measuring the temperature of the ocean.He found that the deeper the water,the colder it got,and he concluded that the seafloor was covered with a thick layer of ice.Péron ignored the fact that water expands when it freezes and that ice therefore floats.A more popular belief at the time was that water at great depth would be compressed to such a density that nothing could sink through it.This ignored the fact that water is all but incompressible.But even the more sensible naturalists of the day were guilty of a similar misconception.They imagined the deep sea as being filled with an unmoving and undisturbable pool of cold,dense water.In reality the deep is always being refreshed by cold water sinking from above.

The central implication of all these misconceptions was that nothing could live in the abyss(deep),just as Forbes’s observations seemed to indicate.But Forbes erred in two ways.One was the particular study site he happened to use as a springboard for his sweeping postulate of a lifeless abyss.Although the Aegean had been the birthplace of marine biology,its depths are now known to be exceptionally lacking in animal diversity.Moreover,through no fault of his own,Forbes was not particularly successful at sampling such life as did exist at the bottom of the Aegean.It was his dredge that was inadequate.Its opening was so small and the holes in the net so large that the dredge inevitably missed animals.Many of those it did catch must have poured out of its open mouth when Forbes reeled it in.His azoic zone,then,was a plausible but wild extrapolation from pioneering but feeble data.

As it turned out,the existence of the azoic zone had been disproved even before Forbes suggested it,and the theory continued to be contradicted regularly throughout its long and influential life.Searching for the Northwest Passage from the Atlantic to the Pacific in 1818,Sir John Ross had lowered his“deep-sea clam”—a sort of bivalved sediment scoop—into the waters of Baffin Bay(an inlet between the Atlantic and Arctic oceans),which he determined to be more than a thousand fathoms deep in some places.Modern soundings indicate he overestimated his depths by several hundred fathoms,but in any case Ross’s clam dove several times deeper than Forbes’s dredge.It brought back mud laced with worms,and starfish that had entangled themselves in the line at depths well below the supposed boundary of the azoic zone.

Question 1

According to paragraph 1,why was the HMS Beacon in the Aegean Sea?

A.To capture creatures along the sea bottom

B.To provide Forbes with transportation back and forth across the Aegean

C.To test the effectiveness of a new type of dredge

D.To carry out a survey of the Aegean Sea

Paragraph 1 is marked with an arrow

正确答案：D

题目详解

题型分类：事实信息题

题干分析：关键词HMS Beacon，Aegean，用关键词可以定位到第一段的第一句In 1841 Edward Forbes was offered the chance to serve as naturalist aboard HMS Beacon,an English Royal Navy ship assigned to survey the Aegean Sea.从同位语可以得出，HMS Beacon是用来调查A海的。

选项分析：

D选项：是原文的同义复述，正确。

A选项：对应文中He collected hundreds of different species of animals，但是这仅仅是他做的一部分工作，与原文无关。

B选项：意思是给F提供来回A海的交通工具，原文未提到，无中生有。

C选项：意思是测试新采集船的有效性。原文未提到，属于无中生有。

Question 2

Which of the sentences below best expresses the essential information in the highlighted sentence in the passage?Incorrect choices change the meaning in important ways or leave out essential information.

A.The hundreds of different species of animals Forbes collected fell into eight distinct groups,each associated with a different depth zone.

B.Forbes realized that depth zones,like elevation zones,contain hundreds of different species.

C.By collecting hundreds of different animals on land and sea,Forbes discovered that there were eight elevation zones and eight depth zones.

D.In addition to collecting different species of animals in eight ocean zones,Forbes collected different species of plants in eight mountain zones.

正确答案：A

题目详解

题型分类：简化句子题

题干分析：画线句译为：他收集了上百种不同种的动物，并且他认为这些动物是分布在八个不同的深度地带的，每个地带所拥有的动物都独一无二，就像随着山的高度不同，所存在的植物种类也不同一样。这句话的主干可以简化为：He collected animals and he saw they were distributed in eight different depth zones.逻辑关系是：他收集了多种动物并进行了分类，从而得出了这些动物按照深度进行分类的结论，这个结论和山上的植被的规律类似。

选项分析：

A选项：在内容上是原文的同义复述，逻辑上正确。

B选项：只说了包含很多物种，没有说这些物种随着深度变化的分类关系，在内容上缺少主干信息。

C选项：提到的elevations和depth zone在原句中分别对应山和海区域，应该是对比的关系，并不是并列关系。Forbes只发现了zones of depth，逻辑和内容均有误。

D选项：中提到Forbes收集了山上的植物，原文中山上的植物只是用来和Forbes收集的海洋动物作类比，并没有收集山上的植物，内容错误。

Question 3

Why does the author mention that Forbes“extended a line on his graph of animal number versus depth”?

A.To indicate how Forbes concluded that some forms of animal life in the depths of the ocean had never been seen before

B.To help explain how Forbes arrived at his theory of the azoic zone

C.To make the point that Forbes was a well-trained professional

D.To show how naturalists of Forbes’s time carried out their research

正确答案：B

题目详解

题型分类：修辞目的题

题干分析：本题考查段落主旨，定位到前一句话：The number of species and individuals diminishes as we descend,pointing to a zero in the distribution of animal life as yet unvisited.意思是物种的数量随着深度增加而减少，最终变成0。往后定位一句话：Below that was the final zone in Forbes's scheme,zone nine,a zone that covered most of the ocean floor and thus most of the solid surface of Earth.意思是在这条线之下是Forbes认为没有动物生存的海底。其中的Below that指代的就是题干中的句子所画的线。根据前后两句话可以得知，Forbes画线是为了得出自己azoic zone的结论，即在这之下没有动物植物能生存。

选项分析：

B选项：帮助解释Forbes如何得出azoic zone的理论，是原文同义复述，正确。

A选项：发现了从未发现的物种，无中生有。

C选项：证明Forbes是训练有素的专家，无中生有。

D选项：展示Forbes那个年代的自然学家如何做实验，原文未提到，无中生有。

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