2014年5月托福考试复习题及答案(第四套)_第4页

　　The geology of the Earth's surface is dominated by the particular properties of water.

　　Present on Earth in solid, liquid, and gaseous states, water is exceptionally reactive. It　dissolves, transports, and precipitates many chemical compounds and is constantly　Line modifying the face of the Earth.　(5) Evaporated from the oceans, water vapor forms clouds, some of which are transported　by wind over the continents. Condensation from the clouds provides the essential agent of　continental erosion: rain. Precipitated onto the ground, the water trickles down to form　brooks, streams, and rivers, constituting what are called the hydrographic network. This　immense polarized network channels the water toward a single recepatcle: an ocean.(10) Gravity dominates this entire step in the cycle because water tends to minimize its　potential energy by running from high altitudes toward the reference point, that is, sea　level.

　　The rate at which a molecule of water passes through the cycle is not random but is a　measure of the relative size of the various reservoirs. If we define residence time as the　(15) average time for a water molecule to pass throught one of the three reservoirs—　atmosphere, continent, and ocean—we see that the times are very different. A water　molecule stays, on average, eleven days in the atmosphere, one hundred years on a　continent and forty thousand years in the ocean. This last figure shows the importance of　the ocean as the principal reservoir of the hydrosphere but also the rapidity of water　(20) transport on the continents.

　　A vast chemical separation process takes places during the flow of water over the　continents. Soluble ions such as calcium, sodium, potassium, and some magnesium are　dissolved and transported. Insoluble ions such as aluminum, iron, and silicon stay where　they are and form the thin, fertile skin of soil on which vegetation can grow. Sometimes(25) soils are destroyed and transported mechanically during flooding. The erosion of the　continents thus results from two closely linked and interdependent processes, chemical　erosion and mechanical erosion. Their respective interactions and efficiency depend on　different factors.

　　8. All of the following are example of soluble ions EXCEPT

　　(A) magnesium

　　(B) iron

　　(C) potassium

　　(D) calcium

　　答案：B

　　The canopy, the upper level of the trees in the rain forest, holds a plethora of climbing　mammals of moderately large size, which may include monkeys, cats, civets, and　porcupines. Smaller species, including such rodents as mice and small squirrels, are not　Line as prevalent overall in high tropical canopies as they are in most habitats globally.(5) Small mammals, being warm blooded, suffer hardship in the exposed and turbulent　environment of the uppermost trees. Because a small body has more surface area per　unit of weight than a large one of similar shape, it gains or loses heat more swiftly.

　　Thus, in the trees, where shelter from heat and cold may be scarce and conditions may　fluctuate, a small mammal may have trouble maintaining its body temperature.　(10) Small size makes it easy to scramble among twigs and branches in the canopy for　insects, flowers, or fruit, but small mammals are surpassed, in the competition for　food, by large ones that have their own tactics for browsing among food-rich twigs.

　　The weight of a gibbon (a small ape) hanging below a branch arches the terminal　leaves down so that fruit-bearing foliage drops toward the gibbon's face. Walking or(15) leaping species of a similar or even larger size access the outer twigs either by snapping off　and retrieving the whole branch or by clutching stiff branches with the feet or tail and　plucking food with their hands.

　　Small climbing animals may reach twigs readily, but it is harder for them than for　large climbing animals to cross the wide gaps from on tree crown to the next that　(20) typify the high canopy. A macaque or gibbon can hurl itself farther than a mouse can: it　can achieve a running start, and it can more effectively use a branch as a springboard,　even bouncing on a limb several times before jumping. The forward movement of a small　animal is seriously reduced by the air friction against the relatively large surface　area of its body. Finally, for the many small mammals that supplement their insect　(25) diet with fruits or seeds, an inability to span open gaps between tree crowns may be　problematic, since trees that yield these foods can be sparse.

　　2. Which of the following animals is less common in the upper canopy than in other environments?

　　(A) Monkeys

　　(B) Cats

　　(C) Porcupines

　　(D) Mice

　　答案：D

　　During the seventeenth and eighteenth centuries, almost nothing was written about the　contributions of women during the colonial period and the early history of the newly　formed United States. Lacking the right to vote and absent from the seats of power,　Line women were not considered an important force in history. Anne Bradstreet wrote some　(5) significant poetry in the seventeenth century, Mercy Otis Warren produced the best　contemporary history of the American Revolution, and Abigail Adams penned important　letters showing she exercised great political influence over her husband, John, the second　President of the United States. But little or no notice was taken of these contributions.

　　During these centuries, women remained invisible in history books.　(10) Throughout the nineteenth century, this lack of visibility continued, despite the efforts　of female authors writing about women. These writers, like most of their male　counterparts, were amateur historians. Their writings were celebratory in nature, and　they were uncritical in their selection and use of sources.

　　During the nineteenth century, however, certain feminists showed a keen sense of　(15) history by keeping records of activities in which women were engaged. National,　regional, and local women's organizations compiled accounts of their doings. Personal　correspondence, newspaper clippings, and souvenirs were saved and stored. These sources　form the core of the two greatest collections of women's history in the United States; one　at the Elizabeth and Arthur Schlesinger Library at Radcliffe College, and the other the　(20) Sophia Smith Collection at Smith College. Such sources have provided valuable　materials for later generations of historians.

　　Despite the gathering of more information about ordinary women during the　nineteenth century, most of the writing about women conformed to the "great women"　theory of history, just as much of mainstream American history concentrated on "great　(25) men." To demonstrate that women were making significant contributions to American　life, female authors singled out women leaders and wrote biographies. or else important　women produced their autobiographies. Most of these leaders were involved in public　life as reformers, activists working for women's right to vote, or authors, and were not　representative at all of the great of ordinary woman. The lives of ordinary people　(30) continued, generally, to be untold in the American histories being published.

　　9. In the last paragraph, the author mentions all of the following as possible roles of nineteenth-century "great women" EXCEPT

　　(A) authors

　　(B) reformers

　　(C) activists for women's rights

　　(D) politicians

　　答案：D