摘要：在日常學習中，我們時常需要做些練習題，而與練習題如影隨形的.則是答案，借助答案我們可以更好地掌握此類題型的解題思路和方法。以下是小編幫

(資料圖片)

在日常學習中，我們時常需要做些練習題，而與練習題如影隨形的.則是答案，借助答案我們可以更好地掌握此類題型的解題思路和方法。以下是小編幫大家整理的托福考試真題及答案，希望可以幫助到有需要的朋友。

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 Fran?ois 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

正確答案：D

題目詳解

題型分類：事實信息題

題干分析：關鍵詞HMS Beacon，Aegean，用關鍵詞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.從同位語可以得出，HMS Beacon是用來調查A海的。

選項分析：

D選項：是原文的同義復述，正確。

A選項：對應文中He collected hundreds of different species of animals，但是這僅僅是他做的一部分工作，與原文無關。

B選項：意思是給F提供來回A海的交通工具，原文未提到，無中生有。

C選項：意思是測試新采集船的有效性。原文未提到，屬于無中生有。

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.

正確答案：A

題目詳解

題型分類：簡化句子題

題干分析：畫線句譯為：他收集了上百種不同種的動物，并且他認為這些動物是分布在八個不同的深度地帶的，每個地帶所擁有的動物都獨一無二，就像隨著山的高度不同，所存在的植物種類也不同一樣。這句話的主干可以簡化為：He collected animals and he saw they were distributed in eight different depth zones.邏輯關系是：他收集了多種動物并進行了分類，從而得出了這些動物按照深度進行分類的結論，這個結論和山上的植被的規律類似。

選項分析：

A選項：在內容上是原文的同義復述，邏輯上正確。

B選項：只說了包含很多物種，沒有說這些物種隨著深度變化的分類關系，在內容上缺少主干信息。

C選項：提到的elevations和depth zone在原句中分別對應山和海區域，應該是對比的關系，并不是并列關系。Forbes只發現了zones of depth，邏輯和內容均有誤。

D選項：中提到Forbes收集了山上的植物，原文中山上的植物只是用來和Forbes收集的海洋動物作類比，并沒有收集山上的植物，內容錯誤。

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

正確答案：B

題目詳解

題型分類：修辭目的題

題干分析：本題考查段落主旨，定位到前一句話：The number of species and individuals diminishes as we descend,pointing to a zero in the distribution of animal life as yet unvisited.意思是物種的數量隨著深度增加而減少，最終變成0。往后定位一句話：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.意思是在這條線之下是Forbes認為沒有動物生存的海底。其中的Below that指代的就是題干中的句子所畫的線。根據前后兩句話可以得知，Forbes畫線是為了得出自己azoic zone的結論，即在這之下沒有動物植物能生存。

選項分析：

B選項：幫助解釋Forbes如何得出azoic zone的理論，是原文同義復述，正確。

A選項：發現了從未發現的物種，無中生有。

C選項：證明Forbes是訓練有素的專家，無中生有。

D選項：展示Forbes那個年代的自然學家如何做實驗，原文未提到，無中生有。