托福-12及答案解析.doc

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1、托福-12 及答案解析(总分：100.04，做题时间：90 分钟)一、READING(总题数：0，分数：0.00)二、passage-1(总题数：1，分数：12.00)EaglesSeen as symbols of strength, courage, determination and immortality since ancient times, eagles are found throughout the world with the exceptions of Antarctica and New Zealand. Eagles are powerful birds renown

2、ed for their keen vision. All eagles have powerful sharp claws called talons, as well as heavy hooked beaks or bills. This combination makes them feared predators as they swoop down from on high and attack small animals such as fish, rodents, birds, snakes, rabbits and even monkeys. The eagle uses i

3、ts powerful talons and beak to tear apart prey that is too heavy to carry. Eagles also sometimes steal the catch of other predatory birds such as ospreys. Most of the 50 species of eagles range in length from 2 to 3 feet and have wingspans of approximately 6 feet. Eagles live in aerial nests, which

4、they build high in trees or on rocky ledges that are inaccessible to other animals. The nest must be kept secure because young eagles are helpless for a long period of time after hatching and remain in the nest for 50 to 100 days depending on the species. Made of sticks and lined with leaves and gra

5、ss, the same nest may be used by a pair of birds for a number of years. The female eagle lays one to three brownish speckled eggs, and these are incubated by either parents or just the female. Young eagles are covered in down and do not develop adult coloration until they reach the age of two. A par

6、ticularly famous species of eagle is the Haliaeetus Leucocephalus or Bald Eagle, which is the national emblem of the United States. The Bald Eagle is not in fact bald, and the moniker was applied because of the contrast between its white head and brown body. The Bald Eagle is extremely rare and for

7、many years it was feared that this magnificent creature would become extinct. However, due to conservation efforts this tragedy has been averted. The Bald Eagle and eagles in general have few natural enemies; it is human beings who are the greatest threat to their survival. The hunting and capture o

8、f eagles for sport, the use of agricultural pesticides and urban encroachment upon their natural habitats have all proved extremely dangerous to the survival of this majestic bird. The exact causes for the slow but steady decline in the number of Bald Eagles around the world is still debatable. Earl

9、y during the seventies, it has been speculated that the widespread use of DTT, a powerful pesticide, is the leading cause behind the demise of this majestic bird species. It seemed that DTT had rendered the Bald Eagle sterile or unable to hatch properly. Its eggshells were far too brittle to survive

10、 adverse weather conditions and cracked open before hatching. However, new studies prove that the thinning eggshells were rather the result of a calcium-deficient diet as eagles fed with the nutrient soon produced more robust eggs. Currently, the number of Bald Eagles shows a steady improvement due

11、mainly to the concerted efforts of conservationists worldwide. Whereas the Bald Eagle“s habitat of choice is the Pacific Northwest and Canada, the largest eagle colony in the world resides in Alaska. Bald Eagles are a favorite species to be observed by birdwatchers across the globe, and one of the c

12、hoice areas for Bald Eagle watching is Squamish by the city of Vancouver. Large eagle colonies come to breed along the Cheakamus River by Squamish during the mild winter months from November to February, and it is not uncommon for some such birds to extend their stay over several seasons when the lo

13、cal salmon population provides enough feeding resources. GlossaryAntarctica: the continent surrounding the South Pole moniker: a person“s name, esp. a nick name or alias（分数：12.00）(1).According to the passage, why are eagles such successful hunters?（分数：3.00）A.They have very large wingspans, which ena

14、ble them to fly over large distances and survey the territory.B.They are ruthless and fierce birds that are not shy of stealing the prey from other predatory birds.C.They are very long animals that are able to fly for a long period of time without getting tired,D.They have powerful and sharp beaks a

15、nd claws with which they rip the flesh off their prey.(2).Why is it important that eagles“ nests cannot be reached by other animals?（分数：3.00）A.so that the female eagle may lay its one to three eggs in peace and quietB.so that the baby eagles are out of harms way until they become able to protect the

16、mselves against other animalsC.so that the birds may safely and quickly deposit their prey at high altitudes on rocky ledges or in treesD.so that the birds may be able to use the same nest year after year over a long period of time(3).What is the main cause behind the Bald Eagle“s thin eggshells?（分数

17、：3.00）A.The unrestrained use of noxious pesticides during the latter part of the last century.B.The extremely frigid weather conditions recorded in certain parts of the world during the seventies.C.The unrestrained hunting of and killing of young bald eagles in their nests.D.The lack of an important

18、 nutrient in the food hunted by Bald Eagles at a certain time in the past.(4).Where do most Bald Eagles reside in the world today?（分数：3.00）A.in the vast expanses of the Alaskan forestB.in northwestern USA and Canada, close to the Pacific OceanC.in the popular Squamish resort by the city of Vancouver

19、D.in the vicinity of the salmon-rich Cheakamus River三、passage-2(总题数：1，分数：12.00)PlutoPluto is unique among the planets in our solar system for several reasons. It was the last planet to be discovered, and is also the smallest and furthest from the Sun. Pluto was discovered in 1930 and has an estimate

20、d diameter of about 1400 miles. Because of its great distance from the Sun, it takes Pluto over 248 years to complete an entire orbit. There is considerable variation in the distance of Pluto from the Sun during the course of its orbit. It gets as close as 2.75 billion miles and travels as far as 4.

21、6 billion miles from the Sun. Because Pluto“s orbit is highly elliptical, its orbit passes within that of Neptune for about 20 years of the time it takes to complete an orbit. Pluto“s great distance from Earth makes it difficult to know with complete certainty its physical characteristics. It is bel

22、ieved that it has a thick methane atmosphere a few kilometers deep and that it is covered with frost and ice. The covering of methane frost is redder towards the equator and bluer at the poles. Pluto is thought to have a large core, likely of silicate rock, which accounts for the planet“s high densi

23、ty. New information is still being learned about Pluto as technology becomes more sophisticated. As recently as 1978, it was discovered that Pluto has a satellite. This satellite, named Charon, has a diameter of about 700 miles and takes just over six days to complete a revolution of Pluto, which is

24、 about the same time that it takes Pluto to complete a rotation. Recently, however, Pluto“s status as a planet has hotly been debated amongst astronomers. More traditional scientists have tried to defend Pluto“s position amongst our solar system“s planetary array on account of traditional values and

25、 beliefs. After all, some argue, it is unfair to downgrade Pluto to a mere asteroid just because of its smaller size when it obviously is a dense corpus with its own satellite. Arguments to the contrary also abound. Many pose that Pluto is a mere object of the Kuiper belt due to the fact that it is

26、constantly pulled into Neptune“s orbital sphere. It is only such drag from a more powerful planet that corrects Pluto“s own course and prevents it from colliding with other celestial bodies. The latter argument won out, and Pluto has recently been removed from textbooks from the list of other planet

27、s of our solar system. GlossaryPluto: the second smallest planet and the farthest known from the sun, has the most elliptical orbit of all the planets elliptical: rounded like an egg silicate: any of numerous compounds containing silicon, oxygen, and one or more metals Charon: the only satellite of

28、Pluto（分数：12.00）(1).According to the passage, why is our knowledge of Pluto not definite?（分数：3.00）A.because Pluto is the smallest planet known to date amongst all celestial bodies of our solar systemB.because no major advances have been made since its incipient discovery in 1930C.because Pluto is so

29、far away from the Earth that it is difficult to observe accuratelyD.because larger planets such as Saturn interfere with its elliptical orbit around the Sun(2).According to the passage, why is Pluto thought to be very dense?（分数：3.00）A.because its middle is made up of a huge chunk of rockB.because it

30、s surface is covered by a thick frost and ice layerC.because its atmospheric layer is more than a few kilometers deepD.because it is located furthest from either the Earth or the Sun(3).Why do traditional scientists believe that Pluto should be considered a planet?（分数：3.00）A.because it would be inco

31、rrect to go against old belief systems and established valuesB.because Pluto is by no accounts just a small and simple asteroid of the solar systemC.because Pluto may be tiny in itself, but is powerful enough to pull a satellite within its orbitD.because Pluto has a well-defined elliptical orbit aro

32、und the sun that intersects Neptune“s orbit(4).Which of the following is true about Pluto not being a planet?（分数：3.00）A.Pluto is in itself not sufficiently dense and powerful to correct its own orbital move and frequently can be thrown off course.B.Pluto has difficulty establishing its place within

33、the Kuiper belt as it is in danger of colliding with other planets.C.Pluto has a very small circumference and is located at the outer edge of the solar system, close to the Kuiper belt.D.Pluto takes more time to complete an entire rotation around the sun than it takes its satellite to revolve around

34、 it.四、passage-3(总题数：1，分数：12.00)Panama CanalThe 50.7-mile long Panama Canal was completed in 1914 with three locks on the Pacific and Atlantic sides. It was first conceived by the Spanish in 1524 when King Charles V ordered a survey of the construction of a waterway across the isthmus. The Panamanian

35、s ultimately gained their independence from Spain and it was not until 1880, when Panama was under control of Columbia, that construction was actually attempted. The Colombian government granted the construction concession to the French Canal Company, whose attempt at construction of a sea level can

36、al ended in bankruptcy nine years later. The rights and assets of the canal were subsequently purchased by the United States for $40 million in 1903, when Panama, with U.S. backing, declared its independence from Columbia. The U.S. paid Panama $I0 million and $250,000 each year for use of the canal.

37、 This yearly sum was tipped in 1933 and 1955, and, in exchange, the U.S. was given control of the Canal Zone, a ten mile strip across the isthmus, as well as substantial influence in Panamanian affairs. In 1977, two treaties were negotiated between the U.S. and Panama to return control of the Canal

38、to Panama. One treaty governs the transfer of the Canal, and the other governs its neutrality following transfer. The Panamanian people approved the treaties by referendum in 1977, and the following year the U.S. Senate gave its approval. The treaties turned control of the canal over to Panama on De

39、cember 31, 1999. According to the treaties, while the U.S. will relinquish control of the Panama Canal, it may intervene with military force to keep the Canal open if it were to become obstructed. The construction of the Panama Canal was determined by economical and political reasons. The French“s i

40、ntention was to exert control over their Caribbean colonies by facilitating access towards French Guyana, which was located at the Northern tip of the South American Continent. Later, the USA wanted to lay territorial claim over the autonomous regions of Puerto Rico and El Salvador, which bordered P

41、anama. They wrestled control of the canal away from Panama and managed to dictate terms in political treatise by closing the canal to commercial traffic and effectively instituting an economic embargo over nations whose commerce depended on navigating its waters. At the time of its opening, the Pana

42、ma Canal was the largest construction of its kind connecting two bodies of water, the Pacific and the Atlantic Ocean. Only the 1869 Suez Canal that was to connect the Red Sea with the Mediterranean would surpass it in length. 18,000 people lost their lives while toiling at the erection of the Panama

43、 Canal, most fatalities having resulted from drowning. Today, the Panama Canal is open to maritime traffic to any commercial or private vessel for a certain fee. Traversing the canal halves the distance between the Atlantic and the Pacific and results in considerable financial and time savings. Glos

44、saryisthmus: a narrow strip of land connecting two larger masses of land concession: a contract granting the right to operate a subsidiary business strip: a long narrow region of land or body of water referendum: the submission of a proposed public measure（分数：12.00）(1).Under whose rule began the con

45、struction of the Panama Canal?（分数：3.00）A.the rule of the Spanish monarch Charles during the 16th centuryB.the rule of the Colombian regime at the end of the 19th centuryC.the rule of the French monarchy during the 1800s colonization periodD.the rule of the U.S, government early during the 20th centu

46、ry(2).What does the 1977 treaty between USA and Panama stipulate?（分数：3.00）A.That the USA should have partial control over the canal in exchange for backing Panama“s bid for independence.B.That the USA should relinquish control of the canal to Panama in exchange for dictating Panama“s foreign policy.

47、C.That the USA should only maintain control over the canal in the exceptional case of military invasion from a foreign power.D.That the USA should transfer the entire control of the canal to Panama in exchange for a promise of neutrality from Panama.(3).What intentions had France and the USA in comm

48、on when they wanted control of the canal?（分数：3.00）A.Both countries wanted free access to the South American nation of Guyana.B.Both countries wanted to invade two strategically located Caribbean nations.C.Both countries wanted absolute power in the Caribbean region bordering northern South America.D

49、.Both countries wanted to impose economical embargos on neighboring countries.(4).What benefit does the Panama Canal bring today?（分数：3.00）A.Ships can cross from one ocean to another in half the usual time.B.Ships can navigate freely within the Caribbean Sea territorial waters.C.Ships can do safe maritime commerce without fear of a military attack.D.Ships can cross both Pacific and Atlantic Ocean without delays.五、passage-4(总题数：1，分数：12.00)EnergyIn industrialized nations, people are using more and more energy all the time so that its demand is ever increasing. Practically everything we do, from