托福-10 (1)及答案解析.doc

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1、托福-10 (1)及答案解析(总分：148.00，做题时间：90 分钟)一、READING(总题数：0，分数：0.00)二、Part 1(总题数：1，分数：6.50)Great Barrier ReefThe Great Barrier Reef is made of coral, a colorful rock-like substance actually composed of many small marine animals, each one less than half a centimeter in size. Coral grows in colonies that can

2、reach over a meter and a half in height, and several of these colonies grow in close proximity to each other, eventually joining up to form an underwater chain or reef. The Great Barrier Reef refers to a series of almost three thousand coral reefs that stretch across the ocean floor in a twelve hund

3、red mile chain, which makes it so long that it can actually be seen from space. Apart from its size, the Great Barrier Reef is also renowned for its age. The living part of the reef itself is around 8,000 years old, but sits atop the remains of dead coral that is much older, in some places almost ha

4、lf a million years old. A system of living organisms so anc ient and so large would be fascinating to scientists by the simple fact of its existence alone, but the Great Barrier Reef is also of great scientific interest because of the diversity of marine life that lives in its vicinity.As stated abo

5、ve, the Great Barrier Reef is made of coral, but just as there are many different varieties of dogs, cats, and finches, there are many varieties of coral, over 500 of which are found in the Great Barrier Reef. The rocky formations of the reefs also provide shelter for a variety of smaller marine fis

6、h, and these in turn provide food for larger, more predatory fish. As a result, some scientists believe that the Reef is home to up to twenty-five percent of all marine fish species. However, this is only a rough estimate since so few of the Reefs fish species have been documented. In addition, the

7、Reef hosts a variety of sponges, anemones, sea turtles, sea snakes, sea birds, and whales. Marine biologists, therefore, value the Reef for what it can teach them about ocean ecology, while other scientists are eagerly investigating the practical applications of chemical compounds produced by the cr

8、eatures of the Reef. Indeed, chemicals initially discovered in Reef organisms are already the basis for many potent new medicines, including some that help battle AIDS and various cancers.Coral reefs in general, and the Great Barrier Reef in particular, have been considered so environmentally import

9、ant that the governments that control the waters where they exist have designated vast tracts of ocean as environmentally protected areas. Nevertheless, the reefs form one giant, interconnected ecosystem, and human activities in unprotected areas of the reefs can affect the entire system. One such h

10、uman activity is fishing. (A) The rich biodiversity of the reefs attracts many predatory fish that in turn draw large numbers of fishing vessels. (B) Unfortunately, many modern fishing techniques employ nets that catch not only the target species, but all fish too big to slip through the holes in th

11、e net. (C) Besides fishing, the reefs face pressure from shipping and oil spills. (D) Shipping can become a problem when freighters make mistakes in navigation and run into the reef,shattering segments of it that have taken decades or even centuries to grow. Oil spills- always damaging to the enviro

12、nment-have an especially devastating effect when they occur near the reefs because so many endangered species are affected.The future of the Great Barrier Reef is uncertain. In addition to the environmental hazards outlined above, the Reef is under threat of global warming. Although coral consists o

13、f tiny, carnivorous animals, those animals do not get most of their nutrients from the organisms they catch. Instead, they enjoy a symbiotic relationship with a form of algae called zooxanthellae. These algae live off the nitrogen emitted by the coral. Like many other types of algae, zooxanthellae u

14、ndergo photosynthesis, using energy from sunlight to create sugars that they can use for fuel. Some of those sugars are also absorbed by the coral that shelter the algae, providing the coral with the fuel it needs to live. However, these particular algae can only perform photosynthesis if the water

15、around them is within a very narrow temperature range. If the temperature of the water in the ocean increases by too much, the algae cease to be able to carry out photosynthesis and are expelled by the coral, which then begins to starve to death. Because it is the presence of zooxanthellae that norm

16、ally gives coral its rich color, coral that has expelled the algae becomes white, leading scientists to term this process “coral bleaching.“（分数：6.50）(1).According to paragraph 1, what is coral made of?（分数：0.50）A.Rocks.B.Colonies.C.Animals.D.Reefs.(2).Which of the following sentences best expresses t

17、he essential information in the highlighted sentence in the passage? Incorrect answer choices change the meaning of the sentence in important ways or leave out essential information.（分数：0.50）A.The size and age of the Great Barrier Reef have caused many scientists to take up residence in its vicinity

18、.B.The Great Barrier Reef is home to a great variety of marine species, according to interested scientists.C.The Great Barrier Reef is scientifically interesting because of its size, age, and ecological diversity.D.Many ancient, large, and scientifically interesting marine organisms live in the vici

19、nity of the Great Barrier Ree(3).What can be inferred from paragraph 1?（分数：0.50）A.Coral first evolved more than 500,000 years ago.B.Scientists are only interested in things both ancient and large.C.Coral is a type of colorful rock that attracts fish.D.No type of coral ever builds a colony more than

20、a meter hig(4).The word “varieties“ in the passage is closest in meaning to（分数：0.50）A.selections.B.ranges.C.similarities.D.types.(5).According to paragraph 2, all of the following are mentioned as living in the Great Barrier Reef EXCEPT（分数：0.50）A.sharks.B.sponges.C.anemones.D.whales.(6).According to

21、 paragraph 2, which of the following is a practical benefit to humanity derived from studying the Great Barrier Reef?（分数：0.50）A.The development of new medicines.B.An increased understanding of ocean ecology.C.A better appreciation of the importance of diversity.D.A cure for the poison of sea snakes.

22、(7).According to paragraph 3, why has designating large segments of the Great Barrier Reef as environmentally protected areas not been wholly effective?（分数：0.50）A.Fishermen and shippers ignore the designation.B.Activity in unprotected areas can influence the whole Reef.C.Oil extracted from the Reef

23、sometimes spills into the ocean.D.The species living there are already endangere(8).The word “vast“ in the passage is closest in meaning to（分数：0.50）A.cosmic.B.infinite.C.extensive.D.limitless.(9).Look at the four squares in the passage that indicate where the following sentence can be added to the p

24、assage.In some areas of the reefs, this has resulted in overfishing that has seriously reduced the diversity of marine life found there.Where would this sentence best fit?（分数：0.50）A. ()B. ()C. ()D. ()(10).The word “they“ in the passage refers to（分数：0.50）A.organisms.B.animals.C.nutrients.D.alga(11).W

25、hy does the author mention “zooxanthellae“?（分数：0.50）A.To demonstrate the full effects of oil spills on the Reef.B.To bolster his argument that the whole Reef needs protection.C.To show how resilient coral is to environmental damage.D.To help explain the phenomenon of coral bleachin(12).The word “ter

26、m“ in the passage is closest in meaning to（分数：0.50）A.express.B.time.C.stretch.D.label.(13).Directions: An introductory sentence for a brief summary of the passage is given below. Complete the summary by adding the THREE answer choices that express the most important ideas in the passage. Some answer

27、 choices do not belong in the summary because they express ideas that are not given in the passage or are minor ideas in the passage. This question is worth 2 points.A series of reefs composed of small animals called coral, the Great Barrier Reef is extremely old and extremely big._Answer Choices1.

28、There are many types of coral, several hundred of which exist as part of the Reef, making it one of the most ecologically diverse places on Earth.2. The Reef is a scientific treasure valued both for what it can contribute to our theoretical understanding of ocean ecology and for what it can yield in

29、 terms of compounds used for creating new medicines.3. Despite efforts to protect large areas of the Reef, the Reef is still threatened by overfishing, shipping accidents, and oil spills.4. The tourist industry also poses a threat to the Reef, since groups of divers visit it on boats that can cause

30、just as much damage to the coral as shipping vessels if they hit it.5. The most recent threat to the Reef comes from global warming, since the rising temperature of the ocean water disrupts the corals symbiotic relationship with a type of algae, causing the coral to turn white and die.6. Coral is qu

31、ite colorful, coming in an array of reds and blues, all generated and maintained by the presence of different varieties of zooxanthellae within the coral.（分数：0.50）填空项 1:_三、Part 2(总题数：2，分数：12.50)Clipper ShipsClipper ships are small, lightweight vessels with three masts that boast a massive array of s

32、ails which allow them to move extremely quickly. The name “clipper“ is thought to come from the fact that the bow of such a ship seems to cut through water as it advances, something also true of older types of ship. Certainly, people were using the expression “to go at a good clip“ to mean “to trave

33、l quickly“ long before the advent of the clipper ship, so the explanation seems to make sense. In fact, it is difficult to date the emergence of the first true clipper, since the word was liberally applied to several speedy ships from the early 19th century that did not possess the technical specifi

34、cations to qualify as clippers under the later definition of the term. What is known, however, is that by the 1840s, several shipyards were engaged in building vessels that were recognizably clipper ships.The great advantage of the clipper ship was its speed. A decently built clipper ship could rout

35、inely cover 250 miles per day, and with good winds, would often travel much faster, in some cases surpassing 400 miles per day. This made the clipper ideal for transporting people from one place to another, since prolonged sea voyages at that time were unpleasant and risky. The clippers were also us

36、ed to transport freight, but in a more limited fashion, since clippers had considerably less cargo space than ordinary freighters of the time. (A) This meant that it was often cheaper to transport durable goods, such as furniture and jewelry, on regular ships that could carry a greater amount of car

37、go, even if it took longer for that cargo to reach its destination. (B) However, for perishable goods, such as spices and teas which would lose their potency over time, clippers proved an immensely profitable method of transport. (C) Clippers were also pressed into service in situations where time w

38、as viewed as more valuable than money. This was the case at the time of the California gold rush, when gold-crazed individuals were determined to be the first to reach what they hoped would be prime prospecting locations. (D)The clipper ship was also used for less respectable activities. Because its

39、 great speed meant that it could outrun or overtake virtually any other type of seafaring vessel known at the time, clippers became the ships of choice for pirates and smugglers. Pirates would use clippers to chase down slower, heavier freighters, then board their victims, transfer the most valuable

40、 pieces of cargo to the clipper, and make a speedy getaway before the authorities could get there. Smugglers could more easily conceal small clippers from prying eyes than they could large sloops, and if discovered, they had a much greater chance of successfully fleeing pursuit. This in turn forced

41、coastal and military authorities to make use of clipper ships as well, simply to keep up with the criminal element. As a result, clippers also became favorites of maritime authorities and privateers. The term “privateers“ refers to those whocrewed ships that were legally entitled by their government

42、s to attack vessels in the service of foreign powers with whom those governments were at war. Unfortunately, privateers operated essentially unsupervised, and it was not uncommon for clippers initially commissioned to guard the seas to turn pirate if the Crew saw an opportunity for a quick profit.Th

43、e era of the clipper was fairly short-lived. Clippers began being built just before the advent of steam-powered boats. These steam-powered boats quickly replaced clippers as the vessels of choice for traders, not because they were faster, since they initially werent, but because they were much more

44、reliable. A clipper, fast as it was, could only make good time with the wind behind it. Headwinds would slow it considerably, and no wind at all would leave it helplessly adrift. A steam boat would often take longer to reach its destination than a clipper would have done, but reach its destination i

45、t would, regardless of the strength and direction of the prevailing winds. The opening of the Suez Canal in 1869 was the final nail in the coffin of commercial clippers, since only steamboats could easily navigate the canal, which shaved thousands of miles off of the journey between Europe and Asia.

46、 In addition, clipper ships were notoriously short-lasting vessels, and most were junked well before reaching twenty years of service, much sooner than the average steamboat. For all of these reasons, by the turn of the 20th century, clipper production had all but ceased.（分数：6.50）(1).According to pa

47、ragraph 1, where does the clipper get its name from?（分数：0.50）A.The great speed at which the ship moves.B.The way the ship cuts through the water.C.The fact that the ship clips time off the trip.D.The use of the word in an early newspaper edition.(2).According to paragraph 1, why is it difficult to d

48、etermine when the first clipper ship was built?（分数：0.50）A.The clipper predates written records by almost 75 years.B.Sailors kept the details of their vessels tightly guarded secrets.C.The clipper has no technical specifications that can be used to identify it.D.The term “clipper“ was originally used

49、 to describe a variety of ships.(3).The word “engaged“ in the passage is closest in meaning to（分数：0.50）A.employed.B.connected.C.appointed.D.slotte(4).According to paragraph 2, what was the most appealing feature of the clipper?（分数：0.50）A.It had the ability to move against the wind.B.It could easily withstand the elements.C.It was sleek and compact.D.It could move really quickly.(5).The word “fashion“ in the passage is closest in