托福TPO33阅读Passage2原文文本+题目+答案解析

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托福TPO30阅读Passage2原文文本+题目+答案解析

托福TPO30阅读Passage2原文文本+题目+答案解析

为了帮助大家高效备考托福,为大家带来托福TPO30阅读Passage2原文文本+题目+答案解析,希望对大家备考有所帮助。

The Pace of Evolutionary Change A heated debate has enlivened recent studiesof evolution.Darwin's original thesis,and theviewpoint supported by evolutionary gradualists,isthat species change continuously but slowly and insmall increments.Such changes are all but invisible over the short time scale of modernobservations,and,it is argued,they are usually obscured by innumerable gaps in theimperfect fossil record.Gradualism,with its stress on the slow pace of change,is a comfortingposition,repeated over and over again in generations of textbooks.By the early twentiethcentury,the question about the rate of evolution had been answered in favor of gradualism tomost biologists'satisfaction. 最近的一个关于进化的研究引发了激烈的争论。

达尔文的原始论点和进化渐进主义者支持的观点是物种会持续地改变,但非常缓慢,增量也很小。

2021年托福阅读PASSAGE 33 试题及答案

2021年托福阅读PASSAGE 33 试题及答案

2021年托福阅读PASSAGE 33试题及答案PASSAGE 33Researchers in the field of psychology have found that one of the best ways to make an important decision, such as choosing a university to attend or a business to invest in, involves the utilization of a decision worksheet. Psychologists who study optimization compare the actual decisions made by people to theoretical ideal decisions to see how similar they are. Proponents of the worksheet procedure believe that it will yield optimal, that is, the best decisions. Although there are several variations on the exact format that worksheets can take, they are all similar in their essential aspects. Worksheets require defining the problem in a clear and concise way and then listing all possible solutions to the problem. Next, the pertinent considerations that will be affected by each decision are listed, and the relative importance of each consideration or consequence is determined. Each consideration is assigned a numerical value to reflect its relative importance. A decision is mathematically calculated by adding these values together. The alternative with the highest number of points emerges as the best decision.Since most important problems are multifaceted, there are several alternatives to choose from, each with unique advantages and disadvantages. One of the benefits of a pencil and paper decision-making procedure is that it permits people to deal with more variables than their minds can generally comprehend and remember. On the average, people can keep about seven ideas in their minds at once. A worksheet can be especially useful when the decision involves a large number of variables with complex relationships. A realistic example for many college students is the question "What will I do after graduation?" A graduate might seek a position that offers specialized training, pursue an advanced degree, or travel abroad for a year.A decision-making worksheet begins with a succinct statement of the problem that will also help to narrow it. It is important to be clear about the distinction between long-range and immediate goals because long-range goals often involve a different decision than short-range ones. Focusing on long-range goals, a graduating student might revise the question above to "What will I do after graduation that will lead to successful career?"1. What does the passage mainly discuss?(A) A tool to assist in making complex decisions.(B) A comparison of actual decisions and ideal decisions(C) Research on how people make decisions(D) Differences between long-range and short-range decision making2. The word "essential" in line 7 is closest in meaning to(A) introductory(B) changeable(C) beneficial(D) fundamental3. The word "pertinent" in line 9 is closest in meaning to(A) relevant(B) preceding(C) insightful(D) responsive4. Of the following steps, which occurs before the others in making a decision worksheet?(A) Listing the consequences of each solution(B) Calculating a numerical summary of each solution(C) Deciding which consequences are most important(D) Writing down all possible solutions5. According to decision-worksheet theory, an optimal decision is defined as one that(A) has the fewest variables to consider(B) uses the most decision worksheets(C) has the most points assigned to it(D) is agreed to by the greatest number of people6. The author develops the discussion in paragraph 1 by means of(A) describing a process(B) classifying types of worksheets(C) providing historical background(D) explaining a theory7. The author states that "On the average, people can keep about seven ideas in their minds at once (lines 17-18) to explain that(A) most decisions involve seven steps(B) human mental capacity has limitations(C) some people have difficulty making minor as well as major decisions(D) people can learn to keep more than seven ideas in their minds with practice8. The word "succinct "in line 24 is closest in meaning to(A) creative(B) satisfactory(C) personal(D) concise9. Which of the following terms is defined in the passage ?(A) Proponents (line 5)(B) Optimal (line 5)(C) Variables (line 17)(D) Long-range goals (line 25)10. The word "it" in line 24 refers to(A) worksheet(B) problem(C) distinction(D) decision11. The word "revise" in line 26 is closest in meaning to(A) ask(B) explain(C) change(D) predictANSWER KEYSPASSAGE 33 ADADC ABDBB C。

托福阅读真题第33套

托福阅读真题第33套

Early Theories of Continental DriftThe idea that the past geography of Earth was different from today is not new.The earliest maps showing the east coast of South America and the west coast of Africa probably provided people with the first evidence that continents may have once been joined together,then broken apart and moved to their present positions.During the late nineteenth century,Austrian geologist Eduard Suess noted the similarities between the Late Paleozoic plant fossils of India,Australia, South Africa,and South America.The plant fossils comprise a unique group of plants that occurs in coal layers just above the glacial deposits on these southern continents.In this book The Face of the Earth(1885),he proposed the name“Gondwanaland”(called Gondwana here)for a supercontinent composed of the aforementioned southern landmasses.Suess thought these southern continents were connected by land bridges over which plants and animals migrated.Thus,in his view,the similarities of fossils on these continents were due to the appearance and disappearance of the connecting land bridges.The American geologist Frank Taylor published a pamphlet in1910 presenting his own theory of continental drift.He explained the formation of mountain ranges as a result of the lateral movements of continents.He also envisioned the present-day continents as parts of larger polar continents that eventually broke apart and migrated toward equator after Earth’s rotation was supposedly slowed by gigantic tidal forces.According to Taylor,these tidal forces were generated when Earth’s gravity captured the Moon about100 million years ago.Although we know that Taylor‘s explanation of continental drift is incorrect,one of his most significant contributions was his suggestion that the Mid-Atlantic Ridge—an underwater mountain chain discovered by the 1872-1876British HMS Challenger expeditions—might mark the site at which an ancient continent broke apart,forming the present-day Atlantic Ocean.However,it is Alfred Wegener,a German meteorologist,who is generally credited with developing the hypothesis of continental drift.In his monumental book,The Origin of Continents and Oceans(1915),Wegener proposed that all landmasses were originally united into a single supercontinent that he named“Pangaea.”Wegner portrayed his grand concept of continental movement in a series of maps showing the breakup of Pangaea and the movement of various continents to their present-day locations.What evidence did Wegener use to support his hypothesis of continental drift?First,Wegener noted that the shorelines of continents fit together,forming a large supercontinent and that marine,nonmarine,and glacial rock sequences of Pennsylvanian to Jurassic ages are almost identical for all Gondwana continents,strongly indicating that they were joined together at one time.Furthermore,mountain ranges and glacial deposits seem to match up in such a way that suggests continents could have once been a single landmass.And last,many of the same extinct plant and animal groups are found today on widely separated continents,indicating that the continents must have been in proximity at one time.Wegener argued that this vast amount of evidence from a variety of sources surely indicated the continents must have been close together at one time in the past.Alexander Du Toit,a South African geologist was one of Wegener’s ardent supporters.He noted that fossils of the Permian freshwater reptile “Mesosaurus”occur in rocks of the same age in both Brazil and South Africa. Because the physiology of freshwater and marine animals is completely different,it is hard to imagine how a freshwater reptile could have swum across the Atlantic Ocean and then found a freshwater environment nearly identical to its former habitat.Furthermore,if Mesosaurus could have swum across the ocean,its fossil remains should occur in other localities besides Brazil and South Africa.It is more logical to assume that Mesosaurus lived in lakes in what are now adjacent areas of South America and Africa but were then united in a single continent.Despite what seemed to be overwhelming evidence presented Wegener and later Du Toit and others,most geologists at the time refused to entertain the idea that the continents might have moved in the pastParagraph2During the late nineteenth century,Austrian geologist Eduard Suess noted the similarities between the Late Paleozoic plant fossils of India,Australia, South Africa,and South America.The plant fossils comprise a unique group of plants that occurs in coal layers just above the glacial deposits on thesesouthern continents.In this book The Face of the Earth(1885),he proposed the name“Gondwanaland”(called Gondwana here)for a supercontinent composed of the aforementioned southern landmasses.Suess thought these southern continents were connected by land bridges over which plants and animals migrated.Thus,in his view,the similarities of fossils on these continents were due to the appearance and disappearance of the connecting land bridges.1.According to paragraph2,Eduard Suess believed that similarities of plantand animal fossils on the southern continents were due toA.living in the southern climateB.crossing the land bridgesC.fossilization in the coal layersD.movements of the supercontinentParagraph3The American geologist Frank Taylor published a pamphlet in1910 presenting his own theory of continental drift.He explained the formation of mountain ranges as a result of the lateral movements of continents.He also envisioned the present-day continents as parts of larger polar continents that eventually broke apart and migrated toward equator after Earth’s rotation was supposedly slowed by gigantic tidal forces.According to Taylor,these tidal forces were generated when Earth’s gravity captured the Moon about100 million years ago.Although we know that Taylor‘s explanation of continental drift is incorrect,one of his most significant contributions was his suggestion that the Mid-Atlantic Ridge—an underwater mountain chain discovered by the 1872-1876British HMS Challenger expeditions—might mark the site at which an ancient continent broke apart,forming the present-day Atlantic Ocean.2.According to paragraph3,Frank Taylor believed thatA.present-day continents broke off from larger continents and drifted towardthe poles due to tidal forcesB.the lateral shifting of continents caused the formation of mountain rangesC.polar continents began to join together when Earth’s gravity captured theMoon100million years agoD.Earth’s gravity and speed of rotation created large polar continents3.Which of the following can be inferred from paragraph3about theMid-Atlantic Ridge?A.It was once above sea level.B.It formed at the same time that Earth’s gravity captured the Moon.C.It was much more extensive when it was first formed than it is today.D.It was unknown before the HMS Challenger voyages.4.The word“generated”in the passage is closest in meaning toA.strengthenedB.releasedC.producedD.presentParagraph4However,it is Alfred Wegener,a German meteorologist,who is generally credited with developing the hypothesis of continental drift.In his monumental book,The Origin of Continents and Oceans(1915),Wegener proposed that all landmasses were originally united into a single supercontinent that he named“Pangaea.”Wegner portrayed his grand concept of continental movement in a series of maps showing the breakup of Pangaea and the movement of various continents to their present-day locations. What evidence did Wegener use to support his hypothesis of continental drift? First,Wegener noted that the shorelines of continents fit together,forming a large supercontinent and that marine,nonmarine,and glacial rock sequences of Pennsylvanian to Jurassic ages are almost identical for all Gondwana continents,strongly indicating that they were joined together at one time. Furthermore,mountain ranges and glacial deposits seem to match up in such a way that suggests continents could have once been a single landmass.And last, many of the same extinct plant and animal groups are found today on widely separated continents,indicating that the continents must have been in proximity at one time.Wegener argued that this vast amount of evidence from a variety of sources surely indicated the continents must have been close together at one time in the past.5.The word“monumental”in the passage is closest in meaning toA.finalB.persuasiveC.well-knownD.great and significant6.The word“portrayed”in the passage is closest in meaning toA.provedB.formedC.depictedD.defended7.The word“vast”in the passage is closest in meaning toA.enormousB.significantC.convincingD.additional8.According to paragraph4,Wegener felt confident that his theory are correctin part becauseA.contemporary scientists were unable to successfully challenge his evidenceB.many different types of evidence seemed to support his theoryC.his theory accounted for phenomena that earlier theories could not explainD.he had used the most advanced techniques available to gather his evidence9.According to paragraph4,Wegener pointed to all of the following insupport of his theory of continental drift EXCEPT:A.Plants and animals now living on some continents appear to be descendedfrom plants and animals that originated on other continents.B.Rock sequences associated with the continents are extremely similar.C.The coastlines of some continents seem to fit together.D.Mountains on some continents would be adjacent to mountains on othercontinents if these continents were joined.Paragraph5Alexander Du Toit,a South African geologist was one of Wegener’s ardent supporters.He noted that fossils of the Permian freshwater reptile “Mesosaurus”occur in rocks of the same age in both Brazil and South Africa. Because the physiology of freshwater and marine animals is completely different,it is hard to imagine how a freshwater reptile could have swum across the Atlantic Ocean and then found a freshwater environmentnearly identical to its former habitat.Furthermore,if Mesosaurus could have swum across the ocean,its fossil remains should occur in other localities besides Brazil and South Africa.It is more logical to assume that Mesosaurus lived in lakes in what are now adjacent areas of South America and Africa but were then united in a single continent.10.Why does the author mention the fact that“the physiology offreshwater and marine animals is completely different”?A.To explain why Du Toit was able to determine that Mesosaurus was afreshwater reptileB.To explain why Du Toit concluded that certain fossils in rocks in Brazil andSouth Africa were those of the same animalC.To cast doubt on the idea that Mesosaurus could have swum from onelandmass to anotherD.To show Du Toit determined which landmass Mesosaurus originated on11.The word“logical”in the passage is closest in meaning toA.satisfactoryB.modernC.reasonableD.popular12.Which of the following can be inferred from paragraph5about the PermianMesosaurus of Brazil and South Africa?A.It was the dominant animal in the habitats in which it livedB.It lived in similar environments in both places.C.It was a weak swimmer compared with other freshwater reptiles.D.Its physiology differed from that of modern freshwater reptiles. Paragraph5Alexander Du Toit,a South African geologist was one of Wegener’s ardent supporters._He noted that fossils of the Permian freshwater reptile “Mesosaurus”occur in rocks of the same age in both Brazil and South Africa.■Because the physiology of freshwater and marine animals is completely different,it is hard to imagine how a freshwater reptile could have swum across the Atlantic Ocean and then found a freshwater environment nearly identical to its former habitat.■Furthermore,if Mesosaurus could have swum across theocean,its fossil remains should occur in other localities besides Brazil and South Africa.■It is more logical to assume that Mesosaurus lived in lakes in what are now adjacent areas of South America and Africa but were then united in a single continent.13.Look at the four squares[■]that indicates where the following sentencecould be added to the passage.In addition to supplying new geological evidence for continental drift,he crafted convincing arguments based on ancient life forms.Where would the sentence best fit?14.Directions:An introductory sentence for a brief summary of the passage isprovides plete the summary by selecting the THREE answer choices that express the most important ideas in the passage.Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage.This question is worth2points.Several theories involving the movement of continents were proposed in the nineteenth and early twentieth centuriesAnswer ChoicesA.Early maps showing the coastlines of South America and Africa inspiredEduard Suess to search for fossil evidence that today’s southern continents had once been joined in a single landmass.B.To Eduard Suess,continental drift accounted for the presence of the sametypes of fossils on different continents that had at times been connected by land bridges.C.Du Toit’s study of the freshwater reptile Mesosaurus added to the alreadyconsiderable body of evidence that Alfred Wegener had gathered in support of the idea of continental drift.D.Frank Taylor expanded on Eduard Suess’s theory of continental drift byarguing that tidal forces100million years ago had broken continents apart and caused the rise of the Mid-Atlantic Ridge.E.Alfred Wegener,who first developed the theory of continental drift arguedthat all landmasses were originally part of a supercontinent that broke upinto separate continents.F.Early theories of continental drift were not widely accepted at the timebecause they failed to explain why continents moved.Early Theories of Continental Drift1.B2.B3.D4.C5.D6.C7.A8.B9.A10.C11.C12.B13. A14.BCEBioluminescence in Marine Creatures At night along the sea’s edge,the ocean sometimes seems to glow,as if lit from within.This glow is the result of bioluminescence,a phenomenon exhibited by many of the sea’s zooplankton.Bioluminescence is the production of cold light through internal biological processes,as opposed to phosphorescence or fluorescence,both of which are re-emitted light that was initially absorbed from an external source.Many of the sea’s creatures,including squid,dinoflagellates,bacteria, worms,crustaceans,and fish,are known to produce light.The process that marine creatures use to create light is like that of the common firefly and similar to that which creates the luminous green color seen in plastic glow sticks, often used as children’s toys or for illumination during nighttime events.When a glow stick in bent,two chemicals mix,react,and create a third substance that gives off light.Bioluminescent organisms do essentially the same thing;they have a substance,called luciferin,that reacts with oxygen in the presence of enzyme,luciferase.When the reaction is complete,a new molecule is formed that gives off light—glowing blue—green in the underwater world.This biologically driven chemical reaction occurs within the organism’s special light-producing cells,called photocyptes,or light-producing organs,called photophores.Probably one of the most complex light-producing systems is that of the squid.Some squid have both photophores and chromatophores(organs for changing color)with their skin,thus enabling them to control both the color and intensity of the light produced.Recent research has also revealed that in some squid and fish,bioluminescent light may be produced by bacteria that live in a mutually beneficial partnership inside the animal’s light organs.How and why bioluminescence occurs is not fully understood;however,in the undersea realm,it appears to be used in a variety of interesting and ingenious ways.The most commonly observed form of bioluminescence in the sea id the pinpoint sparking of light at night that can create cometlike trails behind moving objects.Almost always,this is the result of dinoflagellates reacting to water motion.The relatively short,momentary displays of light may have evolved to startle,distract,or frighten would-be predators.Collection nets brought up from the sea’s depths at night frequently glow green at great distance.Slowly fading green blobs or pulses of light can be seen coming fromthe organisms within,often from gelatinous creatures.This type of light display may be used to stun disorient,or lure prey.Like a wide-eyed deer caught on a road and dazed by headlights,undersea creatures living within the ocean’s darkness may be momentarily disoriented by short flashes of bioluminescent light.Another of the sea’s light-producing organisms is a small copepod(a type of crustacean)named Sapphirina iris.In the water,Sapphirina creates short flashes of a remarkably rich,azure blue light.But its appearance under a microscope is even more spectacular,the living copepod appears as if constructed of delicately handcrafted,multicolored pieces of stained glass. Within the deep sea,some fish also have a dangling bioluminescent lure or a patch of luminescent skin near the mouth,which may be used to entice unsuspecting prey.Other sea creatures have both light-sensing and light-producing organs. These creatures are thought to use bioluminescence as a form of communication or as a means of identifying an appropriate mate.In the lantern fish,the pattern of photophores distinguishes one species from another.In other fish,bioluminescence may help to differentiate males from females.The squid uses light as a means of camouflage.By producing light from the photophores on its underside,the squid can match light form above and become nearly invisible to predators looking up from below.Squid,as well as some of the gelatinous zooplankton,have also been known to release luminescent clouds or strands of organic material,possibly as a decoy to facilitate escape.And finally,because what they eat is often bioluminescent, many of the transparent deep-sea creatures have red or black stomachs to hide the potentially flashing contents of ingested bioluminescent creatures.Without such a blacked-out stomach,their digestive organs would flash like a neon sign that says,“Eat me,eat me!”Paragraph2Many of the sea’s creatures,including squid,dinoflagellates,bacteria, worms,crustaceans,and fish,are known to produce light.The process that marine creatures use to create light is like that of the common firefly and similar to that which creates the luminous green color seen in plastic glow sticks, often used as children’s toys or for illumination during nighttime events.Whena glow stick in bent,two chemicals mix,react,and create a third substance that gives off light.Bioluminescent organisms do essentially the same thing;they have a substance,called luciferin,that reacts with oxygen in the presence of enzyme,luciferase.When the reaction is complete,a new molecule is formed that gives off light—glowing blue—green in the underwater world.This biologically driven chemical reaction occurs within the organism’s special light-producing cells,called photocyptes,or light-producing organs,called photophores.Probably one of the most complex light-producing systems is that of the squid.Some squid have both photophores and chromatophores(organs for changing color)with their skin,thus enabling them to control both the color and intensity of the light produced.Recent research has also revealed that in some squid and fish,bioluminescent light may be produced by bacteria that live in a mutually beneficial partnership inside the animal’s light organs.1.Why does the author mention the common firefly in the passage?A.To relate the light production of marine creature to that of a familiarlight-producing speciesB.To compare the light production of an insect with the more complex lightproduction of marine creaturesC.To provide an example of a species that does not use a chemical reaction toproduce lightD.To support the point that bioluminescence usually occurs at night2.Which of the following statements about the chemical reaction thatproduces bioluminescence is NOT true,according to paragraph2?A.It occurs when luciferin reacts with oxygen.B.It produces a glowing blue-green light.C.It is much like the process by which children’s toys are illuminated.D.It requires organs called chromatophores.3.Paragraph2demonstrates the complexity of certain squid by stating thatA.the squid employs its bioluminescent light to prevent bacteria fromentering its organsB.the squid controls both the color and intensity of the light it producesC.the squid’s light has greater intensity than that of fishD.the squid produces the enzyme luciferase when it produces light4.The phrase“mutually beneficial”in the passage is closest in meaning toA.helpful to one anotherB.generally practicalC.efficiently balancedD.temporary by design5.Which of the following statements about bioluminescent creatures isimplied by paragraph2?A.Bioluminescent creatures cannot produce light if bacteria enter their lightorgans.B.Not all bioluminescent creatures have both photophores andchromatophores.C.Most bioluminescent organisms do not need the enzyme luciferase in orderto produce light.D.Creatures with light-producing organs are much more common than thosethat have only light producing cells.Paragraph3How and why bioluminescence occurs is not fully understood;however,in the undersea realm,it appears to be used in a variety of interesting and ingenious ways.The most commonly observed form of bioluminescence in the sea id the pinpoint sparking of light at night that can create cometlike trails behind moving objects.Almost always,this is the result of dinoflagellates reacting to water motion.The relatively short,momentary displays of light may have evolved to startle,distract,or frighten would-be predators.Collection nets brought up from the sea’s depths at night frequently glow green at great distance.Slowly fading green blobs or pulses of light can be seen coming from the organisms within,often from gelatinous creatures.This type of light display may be used to stun disorient,or lure prey.Like a wide-eyed deer caught on a road and dazed by headlights,undersea creatures living within the ocean’s darkness may be momentarily disoriented by short flashes of bioluminescent light.Another of the sea’s light-producing organisms is a small copepod(a type of crustacean)named Sapphirina iris.In the water,Sapphirina creates short flashes of a remarkably rich,azure blue light.But its appearance under a microscope is even more spectacular,the living copepod appears as if constructed of delicately handcrafted,multicolored pieces of stained glass.Within the deep sea,some fish also have a dangling bioluminescent lure or a patch of luminescent skin near the mouth,which may be used to entice unsuspecting prey.6.The word“ingenious”in the passage is closet in meaning toA.inventiveB.importantC.unusualD.specialized7.According to paragraph3,when do dinoflagellates produce pinpointsparkling displays of light?A.When they are caught in collection netsB.When they are hunting foodC.When there is a sudden movement of the water around themD.When they are stunned or disoriented8.According to paragraph3,what is notable when looking at Sapphirina irisunder a microscope?A.It produces brief flashes of light.B.Its body is a rich azure blue color.C.It has luminescent skin on its mouth.D.It looks as if it is made of glass of many colors.9.Which of the following is NOT mentioned in paragraph3as a possiblereason for the use of bioluminescence?A.To provide a means of lighting the dark marine watersB.To momentarily disorient other creaturesC.To frighten away potential predatorsD.To attract prey10.The word“delicately”in the passage is closet in meaning toA.individuallyB.brilliantlyC.unusuallyD.finelyParagraph4Other sea creatures have both light-sensing and light-producing organs. These creatures are thought to use bioluminescence as a form ofcommunication or as a means of identifying an appropriate mate.In the lantern fish,the pattern of photophores distinguishes one species from another.In other fish,bioluminescence may help to differentiate males from females.The squid uses light as a means of camouflage.By producing light from the photophores on its underside,the squid can match light form above and become nearly invisible to predators looking up from below.Squid,as well as some of the gelatinous zooplankton,have also been known to release luminescent clouds or strands of organic material,possibly as a decoy to facilitate escape.And finally,because what they eat is often bioluminescent, many of the transparent deep-sea creatures have red or black stomachs to hide the potentially flashing contents of ingested bioluminescent creatures. Without such a blacked-out stomach,their digestive organs would flash like a neon sign that says,“Eat me,eat me!”11.According to paragraph4,squid use bioluminescence tomunicate with other squidB.locate matesC.tell males and females apartD.hide from predators12.The word“ingested”in the passage is closet in meaning toA.remainingB.eatenC.livingD.nutritiousParagraph4Other sea creatures have both light-sensing and light-producing organs. These creatures are thought to use bioluminescence as a form of communication or as a means of identifying an appropriate mate.■In the lantern fish,the pattern of photophores distinguishes one species from another.■In other fish,bioluminescence may help to differentiate males from females.■The squid uses light as a means of camouflage.■By producing light from the photophores on its underside,the squid can match light form above and become nearly invisible to predators looking up from below.Squid,as well as some of the gelatinous zooplankton,have also been known to release luminescent clouds or strands of organic material,possibly as a decoy tofacilitate escape.And finally,because what they eat is often bioluminescent, many of the transparent deep-sea creatures have red or black stomachs to hide the potentially flashing contents of ingested bioluminescent creatures.Without such a blacked-out stomach,their digestive organs would flash like a neon sign that says,“Eat me,eat me!”13.Look at the four squares[■]that indicate where the following sentencecould be added to the passageYet,certain species use bioluminescence for exactly the opposite purpose—to blend in with surroundings and become less identifiable.Where would the sentence best fit?14.Directions:An introductory sentence for a brief summary of the passage isprovides plete the summary by selecting the THREE answer choices that express the most important ideas in the passage.Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage.This question is worth2points.Many of the sea’s creatures produce light through bioluminescence.Answer ChoicesA.Bioluminescent creature use a substance called luciferin and an enzyme toproduce light in a biologically driven chemical reaction.B.Bioluminescence can be used to achieve various and sometimes seeminglyopposite goals such as frightening away predators or luring prey.C.Bioluminescence can be used by some sea creatures as a form ofcommunication or as a means of identifying an appropriate mate.D.The majority of bioluminescent creatures are gelatinous in nature,allowingthem to produce light.E.The same bioluminescent creature cannot have both light-sensing andlight-producing organs.F.Sea creatures that eat bioluminescent material possess special chemicalsthat keep their stomach contents from flashing.Bioluminescence in Marine Creatures1.A2.D3.B4.A5.B6.A7.C8.D9.A10.D11.D12.B13. C14.ABC。

托福阅读TPO33(试题+答案+翻译)第3篇:灭绝事件

托福阅读TPO33(试题+答案+翻译)第3篇:灭绝事件

托福阅读TPO33(试题+答案+翻译)第3篇:灭绝事件为了帮助大家备考托福阅读,提高阅读成绩,下面小编给大家带来托福阅读TPO33(试题+答案+翻译)第3篇:灭绝事件,希望大家喜欢!托福阅读TPO33阅读原文Extinction Episodes of the Past【1】It was not until the Cambrian period, beginning about 600 million years ago, that a great proliferation of macroscopic species occurred on Earth and produced a fossil record that allows us to track the rise and fall of biodiversity. Since the Cambrian period, biodiversity has generally risen, but there have been some notable exceptions. Biodiversity collapsed dramatically during at least five periods because of mass extinctions around the globe. The five major mass extinctions receive most of the attention, but they are only one end of a spectrum of extinction events. Collectively, more species went extinct during smaller events that were less dramatic but more frequent. The best known of the five major extinction events, the one that saw the demise of the dinosaurs, is the Cretaceous-Tertiary extinction.【2】Starting about 280 million years ago, reptiles were the dominant large animals in terrestrial environments. In popular language this was the era “when dinosaurs ruled Earth,” when a wide variety of reptile species occupying many ecological niches. However, no group or species can maintain its dominance indefinitely, and when, after over 200 million years, the age of dinosaurs came to a dramatic end about 65 million years ago, mammals began to flourish, evolving from relatively few types of small terrestrial animals into the myriad of diverse species,including bats and whales, that we know today. Paleontologists label this point in Earth’s history as the end of the Cretaceous period and the beginning of the Tertiary period, often abbreviated as the K-T boundary. This time was also marked by changes in many other types of organisms. Overall, about 38 percent of the families of marine animals were lost, with percentages much higher in some groups Ammonoid mollusks went from being very diverse and abundant to being extinct. An extremely abundant set of planktonic marine animals called foraminifera largely disappeared, although they rebounded later. Among plants, the K-T boundary saw a sharp but brief rise in the abundance of primitive vascular plants such as ferns, club mosses, horsetails, and conifers and other gymnosperms. The number of flowering plants (angiosperms) was reduced at this time, but they then began to increase dramatically.【3】What caused these changes? For many years scientists assumed that a cooling of the climate was responsible, with dinosaurs being particularly vulnerable because, like modern reptiles, they were ectothermic (dependent on environmental heat, or cold-blooded). It is now widely believed that at least some species of dinosaurs had a metabolic rate high enough for them to be endotherms (animals that maintain a relatively consistent body temperature by generating heat internally). Nevertheless, climatic explanations for the K-T extinction are not really challenged by the ideas that dinosaurs may have been endothermic, because even endotherms can be affected by a significant change in the climate.【4】Explanations for the K-T extinction were revolutionized in 1980 when a group of physical scientists led by Luis Alvarez proposed that 65 million years ago Earth was stuck by a 10-kilometer-wide meteorite traveling at 90,000 kilometers per hour. They believed that this impact generated a thick cloud of dust that enveloped Earth, shutting out much of the incoming solar radiation and reducing plant photosynthesis to very low levels. Short-term effects might have included huge tidal waves and extensive fires. In other words, a series of events arising from a single cataclysmic event caused the massive extinctions. Initially, the meteorite theory was based on a single line of evidence. At locations around the globe, geologists had found an unusually high concentration of iridium in the layer of sedimentary rocks that was formed about 65 million years ago. Iridium is an element that is usually uncommon near Earth’s surface, but it is abundant in some meteorites. Therefore, Alvarez and his colleagues concludedthat it was likely that the iridium in sedimentary rocks deposited at the K-T boundary had originated in a giant meteorite or asteroid. Most scientist came to accept the meteorite theory after evidence came to light that a circular formation, 180 kilometers in diameter in diameter and centered on the north coast of the Yucatan Peninsula, was created by a meteorite impact about 65 million years ago.托福阅读TPO33阅读试题1.The word "proliferation" in the passage (paragraph 1) is closest in meaning toA.decline.B.extinction.C.increase.D.migration.2.Paragraph 1 supports which of the following statements about life on Earth before the Cambrian period?A.Biodiversity levels were steady, as indicated by the fossilrecord.B.Levels of biodiversity could not be tracked.C.The most dramatic extinction episode occurred.D.Few microscopic species existed.3.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 dominance of dinosaurs came to an end 65 million years ago, at which time mammals began to flourish and diversify.B.Because no group of species can remain dominant forever, mammals became the dominant group when dinosaurs became extinct.C.After being the dominant group for more than 200 million years, the age of dinosaurs came to a dramatic end 65 million years ago.D.The diverse group of mammals that we know today, including bats and whales, evolved from small terrestrial forms that had been dominated by dinosaurs.4.According to paragraph 2, why are dinosaurs popularly said to have "ruled Earth" during the Cretaceous period?A.Dinosaurs were the only species of reptile that existed during the whole of the Cretaceous period.B.Dinosaurs won the battle for food resources over mammals during the Cretaceous period.C.Dinosaurs survived extinction during the Cretaceous period, whereas many other animal species did not.D.Dinosaurs were the physically and ecologically dominant animals during the Cretaceous period.5.According to paragraph 2, which of the following speciesinitially increased in number at the K-T boundary?A.Dinosaurs.B.Foraminifera.C.Ferns.D.Ammonoid mollusks.6.Why does the author note that "even endotherms can be affected by a significant change in the climate"(paragraph 3)?A.To argue that there was a significant climate at the time that endothermic dinosaurs became extinct.B.To argue that climate change caused some dinosaurs to evolve as endotherms.C.To support the view that at least some of the dinosaurs that became extinct were endotherms.D.To defend climate change as possible explanation for the extinction of dinosaurs.7.The word "generated"(paragraph 4) in the passage is closest in meaning toA.collected.B.produced.C.spread.D.added.8.The word "extensive"(paragraph 4) in the passage is closest in meaning toA.widespread.B.sudden.C.numerous.D.subsequent.9.According to paragraph 4, all of the following contributed to the massive extinctions of the K-T period EXCEPT:A.tidal waves.B.fires.C.insufficient solar radiation.D.iridium.10.According to paragraph 4, which of the following statements explains the importance of the discovery of high levels of iridium rocks?A.It provided evidence that overexposure to solar radiation led to the K-T extinction.B.It showed that more than one cataclysmic event was responsible for the K-T extinction.C.It suggested that the cause of the K-T extinction may have been a meteorite striking Earth.D.It provided evidence that the K-T extinction occurred 65 million years ago.11.According to paragraph 4, which of the following is true about the Yucatan Peninsula?A.The circular formation there was caused by a meteorite impact 65 million years ago.B.Sedimentary rocks from that area have the lowest iridium concentration of any rocks on Earth.C.There is evidence that a huge tidal wave occurred there 65 million years ago.D.Evidence found there challenged the meteorite impact theory.12.Which of the following can be inferred from paragraph 4 about the meteorite theory?A.The data originally presented as evidence for the theory were eventually rejected.B.Many scientists did not accept it when it was first proposed.C.It has not been widely accepted as an explanation for theK-T extinction.D.Alvarez subsequently revised it after a circular formation was found in the Yucatan Peninsula.13. Look at the four squares [■] that indicate where the following sentence could be added to the passage. Where would the sentence best fit? This focused on the chemical composition of ancient rocks.Explanations for the K-T extinction were revolutionized in 1980 when a group of physical scientists led by Luis Alvarez proposed that 65 million years ago Earth was stuck by a 10-kilometer-wide meteorite traveling at 90,000 kilometers per hour. They believed that this impact generated a thick cloud of dust that enveloped Earth, shutting out much of the incoming solar radiation and reducing plant photosynthesis to very low levels. Short-term effects might have included huge tidal waves and extensive fires. In other words, a series of events arising from a single cataclysmic event caused the massive extinctions. ■【A】Initially, the meteorite theory was based on a single line of evidence. ■【B】At locations around the globe, geologists had found an unusually high concentration of iridium in the layer of sedimentary rocks that was formed about 65 million years ago. ■【C】Iridium is an element that is usually uncommon near Earth's surface, but it is abundant in some meteorites. ■【D】Therefore, Alvarez and his colleagues concluded that it was likely that the iridium in sedimentary rocks deposited at the K-T boundary had originated in a giant meteorite or asteroid. Most scientist came to accept the meteorite theory after evidence came to light that a circular formation, 180 kilometers in diameter in diameter and centered on the north coast of the Yucatan Peninsula, was created by a meteorite impact about 65 million years ago.14. Prose SummaryThe K-T extinction 65 million years ago is the best known of the five major extinction episodes since the Cambrian period.A.Collectively, the five major extinction episodes resulted in the elimination of a larger number of species than did all the minor extinction events.B.The K-T extinction eliminated the dinosaurs and ammonoid mollusks but was followed by the diversification of mammals and gymnospermous plants.C.An extreme cooling of the climate could not have caused the K-T extinction of dinosaurs, because, while most dinosaurs depended on environmental heat, some did not.D.The K-T extinction of the dinosaurs is the only mass extinction that has been explained by the impact of a meteorite.E.In 1980 Luis Alvarez proposed that the K-T extinction was caused by ecological disasters brought about by the impact of a meteorite striking Earth.F.A high concentration of iridium in sedimentary rocks at the K-T boundary and a large impact crater in the Yucatan Peninsula from 65 million years ago strongly support Alvarez' hypothesis.托福阅读TPO33阅读答案1.proliferation,繁殖,激增,对应C。

托福阅读TPO33-2 Railroads and Commercial Agriculture in Nineteenth-Century United States

托福阅读TPO33-2 Railroads and Commercial Agriculture in Nineteenth-Century United States

Railroads and Commercial Agriculturein Nineteenth-CenturyUnitedStatesBy 1850 the UnitedStatespossessedroughly 9,000 miles of railroadtrack; thenyears later it had over 30,000 miles, more than the restof the world combined. Muchof the new construction during the 1850s occurredwest of the AppalachianMountains –over 2,000miles in the statesof Ohio and Illinois alone.The effect of the newrailroad linesrippled outwardthroughtheeconomy.Farmers along the tracksbegan to specialize in corps that they could market indistantlocations.With their profitsthey purchasedmanufactured goods that earlier they might havemade at home. Before the railroadreachedTennessee, the stateproduced about 25,000 bushels (or 640 tons) ofwheat, which sold forless than 50cents a bushel. Once the railroad came,farmers in the same countiesgrew400,000bushels (over 10,000 tons) and sold their crop ata dollar a bushel.Thenew railroadnetworksshifted the directionof westerntrade. In 1840most northwestern grainwasshipped south down the Mississippi River to thebustlingport of New Orleans. But lowwatermadesteamboattravelhazardous insummer,and ice shut down traffic in winter. Products such as lard, tallow, and cheesequickly spoiled if stored in New Orleans’hot and humidwarehouses. Increasingly,trafficfrom the Midwestflowedwest to east, overthe new rail lines.Chicago becamethe region’s hub, linking the farms of the upper Midwest to NewYork and other eastern citiesby more than 2,000miles of track in 1855. Thus whilethe value of goods shipped byriver to NewOrleans continuedto increase,the South’soverall share ofwesterntradedroppeddramatically.A sharp rise in demand for grainabroad also encouragedfarmers in theNortheastand Midwest to become morecommerciallyoriented. Wheat, whichin1845 commanded $1.08abushel in New YorkCity,fetched $2.46 in 1855; insimilarfashion the price of corn nearlydoubled. Farmersresponded by specializing in cashcrops, borrowing topurchase more land, and investing in equipment to increaseproductivity.As railroad linesfanned out fromChicago,farmers beganto acquire open prairieland in Illinois and then Iowa, putting the fertile, deep black soilinto production.Commercial agriculturetransformedthisremarkabletreelessenvironment.Tosettlersaccustomedtoeastern woodlands, the thousands of squaremiles of tallgrass were anawesome sight. Indian grass,Canada wildrye, and native big bluestemall grew higher than a person. Because eastern plowscould not penetrate thedensely tangled rootsof prairiegrass, the earliestsettlerserectedfarms along theboundary separating the forestfrom the prairie. In 1837,however, John Deerepatented a sharp-cuttingsteelplow that sliced through the sod without soil stickingto the blade. Cyrus McCormickrefined a mechanical reaper that harvestedfourteentimes more wheat with the same amount of labor. By the 1850s McCormick was selling 1,000 reapers a year and could not keep up with demand, while Deere turnedout 10,000 plows annually.The new commercial farming fundamentally altered the Midwestern landscape and the environment.Native Americans hadgrown corn in the region foryears, butnever in such large fields as did latersettlers who became farmers, whosesurpluses were shipped east.Prairiefarmers also introduced new crops that were not part of the earlier ecologicalsystem, notably wheat, along with fruits and vegetables.Native grasseswerereplaced by a small numberof plantscultivated ascommodities. Corn had the best yields, but it wasprimarily usedto feedlivestock.Because breadplayed a keyrole in the American and European diet, wheatbecamethe major cash crop.Tamegrassesreplacednativegrassesinpasturesfor making hay.Westernfarmersaltered the landscapeby reducing the annual fires that hadkept the prairie freefrom trees. In the absence of thesefires,treesreappeared onland not in cultivationand, if undisturbed,eventuallyformed woodlots. The earlierunbroken landscape gaveway to independent farms, each fenced off in a precisecheckerboardpattern.Itwas an artificialecosystem of animals, woodlots, and crops,whose large, uniformlayout made westernfarms more efficient than themore-irregular farms in theEast.1.According to paragraph 1, each of the followingis true about railroad trackintheUnitedStatesEXCEPT:A)In 1850 the UnitedStateshad less than 10,000 miles ofrailroadtrack.B)By the end of the 1850s, Ohio and Illinois containedmorerailroadtrackthanany other state in the country.C)Much of the railroadtrack built in the UnitedStates during the1850swaslocatedwestof the Appalachian Mountain.D)By 1860 therewere more miles ofrailroadtrack in the UnitedStatesthaninany other country.2.It can be inferred from paragraph 2 that the new railroads hadwhich ofthefollowingeffects on farmcommunities?A)Most new farmswerelocated along the tracks.B)Farmersbegan to growwheat as a commercial corp.C)Many farmer decided togrow a wider variety ofcrops.D)Demand for manufactured goods increased among famers.3.The word “bustling”in the passage is closest in meaning toA)famousB)importantC)growingD)busy4.According to paragraph 3, in what waydid the new rail networkschangewesterntrade?A)Northwesternfarmersalmost completelystopped shipping goodsbysteamboat.B)Many western goods began to be shippedeast by way of Chicagoratherthansouth to New Orleans.C)Chicago largely replaced New York and other eastern cities as the finalmarketfor goods forthe West.D)The value of goods shipped westsoon became greater than thevalueofgoods shipped east.5.According to paragraph 3, what was a disadvantage of shipping goodsfromnorthwesternareasto New Orleans?A)There was no reliableway to get goods from NewOrleans to eastern cities.B)The cost of shipping goods by river toNew Orleanscontinued to increase.C)Goods shipped from New Orleans’ neighboring areas had asignificantcompetitiveadvantage because of their lowertransportation costs.D)The temperaturesand humidity.6.Paragraph 4 supports the idea that the price of wheat morethandoubledbetween 1845 and 1855becauseA)the price of corn nearlydoubled during that same periodB)Demand for grainincreased sharplyoutside the UnitedStatesC)Farmers in the Northeast and Midwest began tospecializein cash cropsD)many farmers had borrowedheavily to purchase land and equipmentforraising wheat7.The word “transformed” in the passage is closestin meaning toA)dominatedB)changedC)improvedD)created8.The word “erected”in the passage is closest in meaning toA)lookedforB)livedonC)preferredD)built9.Whydoes author pointout that “Indiangrass,Canada wildrye,andnativebigbluestem all grew higher than a person”?A)To provide a reasonwhy people from the easternwoodlands of theUnitedStateswereimpressed when they saw the prairieB)To identify an obstaclesto the development of the railroad lines fanningoutfrom ChicagoC)To explain why the transformation of the prairiesby commercialagriculturewas so remarkableD)To provide evidence supportingthe claim that the prairieshadfertile,deepblack soil10.According to paragraph 5, the firstsettlersgenerally did not farm openprairieland becauseA)they could not plow it effectively with the tools thatwereavailableB)prairie land was usually very expensive to buyC)the soilalong boundariesbetween the forestand the prairie wasmorefertilethan the soilof the open prairieD)the railroad lineshad notyet reached the open prairie when thefirstsettlersarrived11.The word “surpluses”in the passage is closest in meaning toA)extra goodsB)commercialgoodsC)unprocessedgoodsD)transportable goods12.According to paragraph 8, prairiefarmerschangedthe landscape by doing allofthe followingEXCEPT:A)Reducing annual firesB)Dividing the land into large,regularly-shaped lotsC)Planting trees that eventuallyformed woodlotsD)Fencing off their farms13.Lookat the foursquares[ ]that indicate wherethe following sentence could beaddedto the passage.The problems werenot limited to routesof transport.Where would the sentencebest fit?14.Prose SummaryThe huge expansion of raillines in MidwesternUnitedStatesduring the 1850shad major economic and environmentaleffects.Answer Choices:A)Construction of new rail lines into the Midwest had beeneffectivelystoppedby the Appalachian Mountains, but by 1850 improvedconstructiontechnology had made furtheradvances possible.B)Rail lines to Chicago and on to the Eastmade it easier togetMidwesterngoods to distantmarkets, while growing demandencouraged cropspecialization and led tohigher crop prices.C)Becauseof the growingvolume of traffic coming byrail from theNortheastand Midwest, the value of goods arriving in New Orleans forshipment tomarketsabroadincreaseddramatically.D)Access to rail lines combined with the development of more-efficientfarmingequipment allowed efertileland of the open prairiesto beusedfor large-scalecommercial agriculture.E)Reduction of annual prairiefiresallowedtrees toreappear, and nativegrasseswerereplaced by a fewcommerciallygrown plants as previouslyunbrokengrasslands were dividedintolargefenced fields.F)Native Americans had grown corn on the prairiesforyears but hadnotproduced largesurpluses because the varietiesthey plantedhadfarpooreryields than those introduced by commercialfarmers.。

托福备考托福阅读34套TPO样题+解析+译文32—2Siam,1851-1910

托福备考托福阅读34套TPO样题+解析+译文32—2Siam,1851-1910

托福备考托福阅读34套TPO样题+解析+译⽂32—2Siam,1851-1910托福考试复习TPO 32—2 Siam,1851-1910原⽂:【1】In the late nineteenth century, political and social changes were occurring rapidly in Siam (now Thailand). The old ruling families were being displaced by an evolving centralized government. These families were pensioned off (given a sum of money to live on) or simply had their revenues taken away or restricted; their sons were enticed away to schools for district officers, later to be posted in some faraway province; and the old patron-client relations that had bound together local societies simply disintegrated. Local rulers could no longer protect their relatives and attendants in legal cases, and with the ending in 1905 of the practice of forcing peasant farmers to work part-time for local rulers, the rulers no longer had a regular base for relations with rural populations. The old local ruling families, then, were severed from their traditional social context.【2】The same situation viewed from the perspective of the rural population is even more complex. According to the government's first census of the rural population, taken in 1905, there were about thirty thousand villages in Siam. This was probably a large increase over the figure even two or three decades earlier, during the late 1800s. It is difficult to imagine it now, but Siam's Central Plain in the late 1800s was nowhere near as densely settled as it is today. There were still forests closely surrounding Bangkok into the last half of the nineteenth century, and even at century’s end there were wild elephants and tigers roaming the countryside only twenty or thirty miles away.【3】Much population movement involved the opening up of new lands for rice cultivation. Two things made this possible and encouraged it to happen. First, the opening of the kingdom to the full force of international trade by the Bowring Treaty (1855) rapidly encouraged economic specialization in the growing of rice, mainly to feed the rice-deficient portions of Asia (India and China in particular). The average annual volume of rice exported from Siam grew from under 60 million kilograms per year in the late 1850s to more than 660 million kilograms per year at the turn of the century; and over the same period the average price per kilogram doubled. During the same period, the area planted in rice increased from about 230,000 acres to more than 350,000 acres. This growth was achieve as the result of the collective decisions of thousands of peasants families to expand the amount of land they cultivated, clear and plant new land, or adopt more intensive methods of agriculture.【4】They were able to do so because of our second consideration. They were relatively freer than they had been half a century earlier. Over the course of the Fifth Reign (1868-1910), the ties that bound rural people to the aristocracy and local ruling elites were greatly reduced. Peasants now paid a tax on individuals instead of being required to render labor service to the government. Under these conditions, it made good sense to thousands of peasant families to in effect work full-time at what they had been able to do only part-time previously because of the requirement to work for the government: grow rice for the marketplace.【5】Numerous changes accompanied these developments. The rural population both dispersed and grew, and was probably less homogeneous and more mobilethan it had been a generation earlier. The villages became more vulnerable to arbitrary treatment by government bureaucrats as local elites now had less control over them. By the early twentieth century, as government modernization in a sense caught up with what had been happening in the countryside since the 1870s, the government bureaucracy intruded more and more into village life. Provincial police began to appear, along with district officers and cattle registration and land deeds and registration for compulsory military service. Village handicrafts diminished or died out completely as people bought imported consumer goods, like cloth and tools, instead of making them themselves. More economic variation took shape in ruralvillages, as some grew prosperous from farming while others did not. As well as can be measured, rural standards of living improved in the Fifth Reign. But the statistical averages mean little when measured against the harsh realities of peasant life.题⽬:1.The word "severed" in the passage (paragraph 1) is closest in meaning toA.cut off.B.viewed.C.protected.D.rescued.2.According to paragraph 1, the situation for Siam's old ruling families changed in all of the following ways EXCEPT:A.Their incomes were reduced.B.Their sons were posted as district officers in distant provinces.C.They could sell lands that had traditionally belonged to them.D.They had less control over the rural populations.3.According to paragraph 2, which of the following was true of Siam in 1905?A.Its urban population began to migrate out of the cities and into the country.B.Its Central Plain was almost as densely populated as it is today.C.It was so rural that wild elephants and tigers sometimes roamed Bangkok.D.It had many more villages than it did in the late 1800s.4.The phrase "rice-deficient portions" in the passage (paragraph 3) is closest in meaning toA.the parts that consume rice.B.the parts that do not have enough rice.C.the parts where rice is grown.D.the parts that depend primarily on rice.5.Paragraph 3 mentions all of the following as signs of economic growth in Siam EXCEPTA.an increase in the price of rice.B.an increase in the amount of rice leaving Siam.C.an increase in the nutritional quality of the rice grown.D.an increase in the amount of land used for rice production.6.According to paragraph 3, farming families increased the amount of rice they grewA.growing varieties of rice that produced greater yields.B.forming collective farms by joining together with other farm families.C.planting rice in areas that had previously remained unplanted.D.hiring laborers to help them tend their fields.7.According to paragraph 4, what happened after the government ended the practice of requiring rural people to perform labor for it?A.Rural people became more closely connected to the aristocracy.B.Rural people spent more time growing rice for profit.C.The government began to pay the laborers who grew rice for it.D.The government introduced a special tax on rice.8.Which of the following best describes the relationship between paragraphs 3 and4 in the passage?A.Paragraph 4 provides further evidence of the economic growth of Siam discussed in paragraph 3.B.Paragraph 4 continues the discussion begun in paragraph 3 of farming improvements that led to economic growth.C.Paragraph 4 examines a particular effect of the Bowring Treaty mentioned in paragraph 3.D.Paragraph 4 discusses the second of two factors that contributed to the expansion of rice farming mentioned in paragraph 3.9.The word "dispersed" in the passage (paragraph 5) is closest in meaning toA.spread out.B.gained power.D.specialized.10.The word "compulsory" in the passage (paragraph 5) is closest in meaning toA.foreign.B.formal.C.required.D.preferred.11.According to paragraph 5, which of the following was true of Siam's rural people during the Fifth Reign?A.They were forced to spend most of the profits from rice growing on registrations required by the government.B.Their lives remained very difficult even though statistics suggest that their quality of life improved.C.The non-farmers among them were helped by the government more than the farmers among them were.D.They were more prosperous when they were ruled by local elites than when they were ruled by the more modern government of the Fifth Reign.12.According to paragraph 5, the government bureaucracy intruded in village life byA.requiring the people to register their cattle and land.B.requiring the people to buy certain kinds of imported goods.C.discouraging the people from making handicrafts and tools.D.encouraging more people to take up farming.13. Look at the four squares [■] that indicate where the following sentence could be added to the passage. Where does the sentence best fit? And yet, how is it that the peasants were able to choose to expand their economic activity in response to the market opportunities?■【A】They were able to do so because of our second consideration.■【B】They were relatively freer than they had been half a century earlier.■【C】Over the course of the Fifth Reign (1868-1910), the ties that bound rural people to the aristocracy and local ruling elites were greatly reduced. Peasants now paid a tax on individuals instead of being required to render labor service to the government.■【D】Under these conditions, it made good sense to thousands of peasant families to in effect work full-time at what they had been able to do only part-time previously because of the requirement to work for the government: grow rice for the marketplace. 14. Prose SummaryDuring the late nineteenth century, changes in Siam's power structure had important economic consequences.A.Population movement occurred and rice cultivation intensified because Siam became more actively involved in international trade.B.Changes in taxation and the ending of the requirement that people work part-time for the rulers allowed farmers to produce more rice for the marketplace.C.Population increases occurred in part because Siam's farmers were able to produce more rice to feed the population. /doc/48bba030f9c75fbfc77da26925c52cc58ad690d7.html nd became so valuable that villagers had to pay the government for the land that they worked on.E.Although rural living standards may have improved somewhat, prosperity varied from village to village and government bureaucracy played a greater role in village life./doc/48bba030f9c75fbfc77da26925c52cc58ad690d7.html ernment modernization in the early twentieth century resulted in the loss of some freedoms that the rural population had gained from the traditional ruling classes.答案:1.sever表⽰"分离,切开",对应cut off。

托福TPO3阅读Passage2原文文本+题目+答案解析

托福TPO3阅读Passage2原文文本+题目+答案解析

为了帮助大家高效备考托福,为大家带来托福TPO3阅读Passage2原文文本+题目+答案解析,希望对大家备考有所帮助。

▉托福TPO3阅读Passage2原文文本: Depletion of the Ogallala Aquifer The vast grasslands of the High Plains in the central United States were settled by farmers and ranchers in the 1880s. This region has a semiarid climate, and for 50 years after its settlement, it supported a low-intensity agricultural economy of cattle ranching and wheat farming. In the early twentieth century, however, it was discovered that much of the High Plains was underlain by a huge aquifer (a rock layer containing large quantities of groundwater). This aquifer was named the Ogallala aquifer after the Ogallala Sioux Indians, who once inhabited the region. The Ogallala aquifer is a sandstone formation that underlies some 583,000 square kilometers of land extending from northwestern Texas to southern South Dakota. Water from rains and melting snows has been accumulating in the Ogallala for the past 30,000 years. Estimates indicate that the aquifer contains enough water to fill Lake Huron, but unfortunately, under the semiarid climatic conditions that presently exist in the region, rates of addition to the aquifer are minimal, amounting to about half a centimeter a year. The first wells were drilled into the Ogallala during the drought years of the early 1930s. The ensuing rapid expansion of irrigation agriculture, especially from the 1950s onward, transformed the economy of the region. More than 100,000 wells now tap the Ogallala. Modern irrigation devices, each capable of spraying 4. 5 million liters of water a day, have produced a landscape dominated by geometric patterns of circular green islands of crops. Ogallala water has enabled the High Plains region to supply significant amounts of the cotton, sorghum, wheat, and corn grown in the United States. In addition, 40 percent of American grain-fed beef cattle are fattened here. This unprecedented development of a finite groundwater resource with an almost negligible natural recharge rate—that is, virtually no natural water source to replenish the water supply—has caused water tables in the region to fall drastically. In the 1930s, wells encountered plentiful water at a depth of about 15 meters; currently, they must be dug to depths of 45 to 60 meters or more. In places, the water table is declining at a rate of a meter a year, necessitating the periodic deepening of wells and the use of ever-more-powerful pumps. It is estimated that at current withdrawal rates, much of the aquifer will run dry within 40 years. The situation is most critical in Texas, where the climate is driest, the greatest amount of water is being pumped, and the aquifer contains the least water. It is projected that the remaining Ogallala water will, by the year 2030, support only 35 to 40 percent ofthe irrigated acreage in Texas that is supported in 1980. The reaction of farmers to the inevitable depletion of the Ogallala varies. Many have been attempting to conserve water by irrigating less frequently or by switching to crops that require less water. Others, however, have adopted the philosophy that it is best to use the water while it is still economically profitable to do so and to concentrate on high-value crops such as cotton. The incentive of the farmers who wish to conserve water is reduced by their knowledge that many of their neighbors are profiting by using great amounts of water, and in the process are drawing down the entire region’s water supplies. In the face of the upcoming water supply crisis, a number of grandiose schemes have been developed to transport vast quantities of water by canal or pipeline from the Mississippi, the Missouri, or the Arkansas rivers. Unfortunately, the cost of water obtained through any of these schemes would increase pumping costs at least tenfold, making the cost of irrigated agricultural products from the region uncompetitive on the national and international markets. Somewhat more promising have been recent experiments for releasing capillary water (water in the soil) above the water table by injecting compressed air into the ground. Even if this process proves successful, however, it would almost triple water costs. Genetic engineering also may provide a partial solution, as new strains of drought-resistant crops continue to be developed. Whatever the final answer to the water crisis may be, it is evident that within the High Plains, irrigation water will never again be the abundant, inexpensive resource it was during the agricultural boom years of the mid-twentieth century. ▉托福TPO3阅读Passage2题目: Question 1 of 14 According to paragraph 1, which of the following statements about the High Plains is true? A. Until farmers and ranchers settled there in the 1880s, the High Plains had never been inhabited.. B. The climate of the High Plains is characterized by higher-than-average temperatures.. C. The large aquifer that lies underneath the High Plains was discovered by the Ogallala Sioux Indians.. D. Before the early 1900s there was only a small amount of farming and ranching in the High Plains..。

托福TPO32阅读Passage2原文文本+题目+答案解析

托福TPO32阅读Passage2原文文本+题目+答案解析
为了帮助大家高效备考托福,为大家带来托福 TPO32 阅读 Passage2 原文文本+题目+答案 解析,希望对大家备考有所帮助。
Siam,1851–1910
In the late nineteenth century,political and social changes were occurring rapidly in Siam(now Thailand).The old ruling families were being displaced by an evolving centralized government.These families were pensioned off(given a sum of money to live on)or simply had their revenues taken away or restricted;their sons were enticed away to schools for district officers,later to be posted in some faraway provinces;and the old patron-client relations that had bound together local societies simply disintegrated.Local rulers could no longer protect their relatives and attendants in legal cases,and with the ending in 1905 of the practice of forcing peasant farmers to work part-time for local rulers,the rulers no longer had a regular base for relations with rural populations.The old local ruling families,then,were severed from their traditional social context.

托福TPO33阅读Passage2原文文本+题目+答案解析

托福TPO33阅读Passage2原文文本+题目+答案解析

托福TPO33阅读Passage2原文文本+题目+答案解析为了帮助大家高效备考托福,为大家带来托福TPO33阅读Passage2原文文本+题目+答案解析,希望对大家备考有所帮助。

Railroads and Commercial Agriculture in Nineteenth-Century United StatesBy 1850 the United States possessed roughly 9,000 miles of railroad track;then years later it had over 30,000 miles,more than the rest of the world combined.Much of the new construction during the 1850s occurred west of the Appalachian Mountains–over 2,000 miles in the states of Ohio and Illinois alone.The effect of the new railroad lines rippled outward through the economy.Farmers along the tracks began to specialize in corps that they could market in distant locations.With their profits they purchased manufactured goods that earlier they might have made at home.Before the railroad reached Tennessee,the state produced about 25,000 bushels(or 640 tons)of wheat,which sold for less than 50 cents a bushel.Once the railroad came,farmers in the same counties grew 400,000 bushels(over 10,000 tons)and sold their crop at a dollar a bushel.The new railroad networks shifted the direction of western trade.In 1840 most northwestern grain was shipped south down the Mississippi River to the bustling port of New Orleans.But low water made steamboat travel hazardous in summer,and ice shut down traffic in winter.Products such as lard,tallow,and cheese quickly spoiled if stored in New Orleans’hot and humid warehouses.Increasingly,traffic from the Midwest flowed west to east,over the new rail li nes.Chicago became the region’s hub,linking the farms of the upper Midwest to New York and other eastern cities by more than 2,000 miles of track in1855.Thus while the value of goods shipped by river to New Orleans continued to increase,the South’s overal l share of western trade dropped dramatically.A sharp rise in demand for grain abroad also encouraged farmers in the Northeast and Midwest to become more commercially oriented.Wheat,which in 1845 commanded$1.08 a bushel in New York City,fetched$2.46 in 1855;in similar fashion the price of corn nearly doubled.Farmers responded by specializing in cash crops,borrowing to purchase more land,and investing in equipment to increase productivity.As railroad lines fanned out from Chicago,farmers began to acquire open prairie land in Illinois and then Iowa,putting the fertile,deep black soil into production.Commercial agriculture transformed this remarkable treeless environment.T o settlers accustomed to eastern woodlands,the thousands of square miles of tall grass were an awesome sight.Indian grass,Canada wild rye,and native big bluestem all grew higher than a person.Because eastern plows could not penetrate the densely tangled roots of prairie grass,the earliest settlers erected farms along the boundary separating the forest from the prairie.In 1837,however,John Deere patented a sharp- cutting steel plow that sliced through the sod without soil sticking to the blade.Cyrus McCormick refined a mechanical reaper that harvested fourteen times more wheat with the same amount of labor.By the 1850s McCormick was selling 1,000 reapers a year and could not keep up with demand,while Deere turned out 10,000 plows annually.The new commercial farming fundamentally altered the Midwestern landscape and the environment.Native Americans had grown corn in the region for years,but never in such largefields as did later settlers who became farmers,whose surpluses were shipped east.Prairie farmers also introduced new crops that were not part of the earlier ecological system,notably wheat,along with fruits and vegetables.Native grasses were replaced by a small number of plants cultivated as commodities.Corn had the best yields,but it was primarily used to feed livestock.Because bread played a key role in the American and European diet,wheat became the major cash crop.Tame grasses replaced native grasses in pastures for making hay.Western farmers altered the landscape by reducing the annual fires that had kept the prairie free from trees.In the absence of these fires,trees reappeared on land not in cultivation and,if undisturbed,eventually formed woodlots.The earlier unbroken landscape gave way to independent farms,each fenced off in a precise checkerboard pattern.It was an artificial ecosystem of animals,woodlots,and crops,whose large,uniform layout made western farms more efficient than the more-irregular farms in the East.译文:十九世纪美国的铁路和商品农业在1850年之前美国有约9,000英里铁轨,几年之后铁轨的长度增加到30,000多英里,比世界上其他地方的总和还要多。

托福阅读TPO32

托福阅读TPO32

托福阅读TPO32查看托福口语TPO1-34文本+MP3,请点击:托福TPO口语大全查看托福阅读TPO1-33阅读原文+题目+答案,请点击:托福TPO阅读大全查看托福听力TPO1-30原文+题目+MP3音频下载,请点击:托福TPO听力大全查看托福写作TPO1-25文本大全,请点击:托福TPO写作大全托福阅读TPO32第1篇:Plant ColonizationColonization is one way in which plants canchange the ecology of a site. Colonization is aprocess with two components: invasion andsurvival. The rate at which a site is colonized byplants depends on both the rate at which individualorganisms (seeds, spores, immature or mature individuals) arrive at the site and their successat becoming established and surviving. Success in colonization depends to a great extent onthere being a site available for colonization—a safe site where disturbance by fire or bycutting down of trees has either removed competing species or reduced levels of competitionand other negative interactions to a level at which the invading species can becomeestablished. For a given rate of invasion, colonization of a moist, fertile site is likely to bemuch more rapid than that of a dry, infertile site because of poor survival on the latter. Afertile, plowed field is rapidly invaded by a large variety of weeds, whereas a neighboringconstruction site from which the soil has beencompacted or removed to expose a coarse,infertile parent material may remain virtually free of vegetation for many months or even yearsdespite receiving the same input of seeds as the plowed field.殖民化是植物能够改变一个地方生态的一种方法。

托福TPO33综合写作阅读原文+听力原文+满分范文

托福TPO33综合写作阅读原文+听力原文+满分范文

为了帮助大家高效备考托福,为大家带来托福TPO33综合写作阅读原文+听力原文+满分范文,希望对大家备考有所帮助。

托福TPO33综合写作阅读原文文本: Carved stone balls are a curious type of artifact found at a number of locations in Scotland. They date from the late Neolithic period, around 4,000 years ago. They are round in shape; they were carved from several types of stone; most are about 70 mm in diameter; and many are ornamented to some degree. Archaeologists do not agree about their purpose and meaning, but there are several theories. One theory is that the carved stone balls were weapons used in hunting or fighting. Some of the stone balls have been found with holes in them, and many have grooves on the surface. It is possible that a cord was strung through the holes or laid in the grooves around the ball. Holding the stone balls at the end of the cord would have allowed a person to swing it around or throw it. A second theory is that the carved stone balls were used as part of a primitive system of weights and measures. The fact that they are so nearly uniform in size – at 70 mm in diameter – suggests that the balls were interchangeable and represented some standard unit of measure. They could have been used as standard weights to measure quantities of grain or other food, or anything that needed to be measured by weight on a balance or scale for the purpose of trade.A third theory is that the carved stone balls served a social purpose as opposed to a practical or utilitarian one. This view is supported by the fact that many stone balls have elaborate designs. The elaborate carving suggests that the stones may have marked the important social status of their owners. 托福TPO33综合写作听力原文文本: None of the three theories presented in the reading passage are very convincing.First, the stone balls as hunting weapons, common Neolithic weapons such as arrowheads and had axes generally show signs of wear, so we should expect that if the stone balls had been used as weapons for hunting of fighting, they too would show signs of that us. Marry of the stone balls would be cracked or have pieces broken off. However, the surfaces of the balls are generally well preserved, showing little or no wear or damage.Second, the carved stone balls maybe remarkably uniform in size, but their masses vary too considerably to have been sued as uniform weights. This is because the stone balls were made of different types of stone including sandstone, green stone and quartzite. Each type of stone has a different density. Some types of stone are heavier than others just as a handful of feathers weighs less than a handful of rocks. Two balls of the same size are different weights depending on the type of stone they are made of. Therefore, the balls could not have been used as a primitive weighing system.Third, it's unlikely that the main purpose of the balls was as some kind of social marker. A couple of facts are inconsistent with this theory. For one thing, while some of the balls are carved with intricate patterns, many others have markings that are extremely simple, too simple to make the balls look like statussymbols. Furthermore, we know that in Neolithic Britain, when someone died, particularly a high-ranking person, they were usually buried with their possessions. However, none of the carved stone balls have been actually found in tombs or graves. That makes it unlikely that the balls were personal possessions that marked a person's status within the community. 托福TPO33综合写作满分范文: The author in the reading passage explores three major functions of the carved stone balls. However, in the lecture, the professor respectively contradicts all his assertions by using three specific points as supports. First, even though the reading passage suggests that the stone balls were weapons because of the holes and grooves on their surface, the professor argues that the stone balls didn’t show signs of use, which means they are neither cracked nor broken and thus cannot be used as weapons. Second, despite the statement in the reading passage that the stone balls were used as primitive weighing system due to their uniform size, the professor contends that their masses vary too considerably from each other. Therefore, the balls could not function as weighing system. Third, the author asserts that the stone balls served a social purpose owing to their elaborate designs while the professor proves that this claim is indefensible by pointing out that the balls were carved with not only intricate patterns but also simple ones, besides, none of the balls were found in the ancient tombs or graves. Consequently, it’s impossible that the balls were social markers. 以上是给大家整理的托福TPO33综合写作阅读原文+听力原文+满分范文,希望对你有所帮助!。

托福备考托福阅读34套TPO样题+解析+译文TPO 33—2 铁路和商品化农业

托福备考托福阅读34套TPO样题+解析+译文TPO 33—2  铁路和商品化农业

托福考试 复习TPO 33—2 铁路和商品化农业原文:Railroads and Commercial Agriculture in Nineteenth-Century United States【1】By 1850 the United States possessed roughly 9,000 miles of railroad track; Ten years later it had over 30,000 miles, more than the rest of the world combined. Much of the new construction during the 1850s occurred west of the Appalachian Mountains—over 2,000 miles in the states of Ohio and Illinois alone.【2】The effect of the new railroad lines rippled outward through the economy. Farmers along the tracks began to specialize in corps that they could market in distant locations. With their profits they purchased manufactured goods that earlier they might have made at home. Before the railroad reached Tennessee, the state produced about 25,000 bushels (or 640 tons) of wheat, which sold for less than 50 cents a bushel. Once the railroad came, farmers in the same counties grew 400,000 bushels (over 10,000 tons) and sold their crop at a dollar a bushel.【3】The new railroad networks shifted the direction of western trade. In 1840 most northwestern grain was shipped south down the Mississippi River to the bustling port of New Orleans. But low water made steamboat travel hazardous in summer, and ice shut down traffic in winter. Products such as lard, tallow, and cheese quickly spoiled if stored in New Orleans’ hot and humid warehouses. Increasingly, traffic from the Midwest flowed west to east, over the new rail lines. Chicago became the region’s hub, linking the farms of the upper Midwest to New York and other eastern cities by more than 2,000 miles of track in 1855. Thus while the value ofgoods shipped by river to New Orleans continued to increase, the South’s overall share of western trade dropped dramatically.【4】A sharp rise in demand for grain abroad also encouraged farmers in the Northeast and Midwest to become more commercially oriented. Wheat, which in 1845 commanded $1.08 a bushel in New York City, fetched $2.46 in 1855; in similar fashion the price of corn nearly doubled. Farmers responded by specializing in cash crops, borrowing to purchase more land, and investing in equipment to increase productivity.【5】As railroad lines fanned out from Chicago, farmers began to acquire open prairie land in Illinois and then Iowa, putting the fertile, deep black soil into production. Commercial agriculture transformed this remarkable treeless environment. To settlers accustomed to eastern woodlands, the thousands of square miles of tall grass were an awesome sight. Indian grass, Canada wild rye, and native big bluestem all grew higher than a person. Because eastern plows could not penetrate the densely tangled roots of prairie grass, the earliest settlers erected farms along the boundary separating the forest from the prairie. In 1837, however, John Deere patented a sharp-cutting steel plow that sliced through the sod without soil sticking to the blade. Cyrus McCormick refined a mechanical reaper that harvested fourteen times more wheat with the same amount of labor. By the 1850s McCormick was selling 1,000 reapers a year and could not keep up with demand, while Deere turned out 10,000 plows annually.【6】The new commercial farming fundamentally altered the Midwestern landscapeand the environment. Native Americans had grown corn in the region for years, but never in such large fields as did later settlers who became farmers, whose surpluses were shipped east. Prairie farmers also introduced new crops that were not part of the earlier ecological system, notably wheat, along with fruits and vegetables. 【7】Native grasses were replaced by a small number of plants cultivated as commodities. Corn had the best yields, but it was primarily used to feed livestock. Because bread played a key role in the American and European diet, wheat became the major cash crop. Tame grasses replaced native grasses in pastures for making hay.【8】Western farmers altered the landscape by reducing the annual fires that had kept the prairie free from trees. In the absence of these fires, trees reappeared on land not in cultivation and, if undisturbed, eventually formed woodlots. The earlier unbroken landscape gave way to independent farms, each fenced off in a precise checkerboard pattern. It was an artificial ecosystem of animals, woodlots, and crops, whose large, uniform layout made western farms more efficient than the more-irregular farms in the East.题目:1.According to paragraph 1, each of the following is true about railroad track in the United States EXCEPT:A.In 1850 the United States had less than 10,000 miles of railroad track.B.By the end of the 1850s, Ohio and Illinois contained more railroad track than anyother state in the country.C.Much of the railroad track built in the United States during the 1850s was located west of the Appalachian Mountain.D.By 1860 there were more miles of railroad track in the United States than in any other country.2.It can be inferred from paragraph 2 that the new railroads had which of the following effects on farm communities?A.Most new farms were located along the tracks.B.Farmers began to grow wheat as a commercial corp.C.Many farmers decided to grow a wider variety of crops.D.Demand for manufactured goods increased among farmers.3.The word "bustling" in the passage (paragraph 3) is closest in meaning toA.famous.B.important.C.growing.D.busy.4.According to paragraph 3, in what way did the new rail networks change western trade?A.Northwestern farmers almost completely stopped shipping goods by steamboat.B.Many western goods began to be shipped east by way of Chicago rather than south to New Orleans.C.Chicago largely replaced New York and other eastern cities as the final market forgoods for the West.D.The value of goods shipped west soon became greater than the value of goods shipped east.5.According to paragraph 3, what was a disadvantage of shipping goods from northwestern areas to New Orleans?A.There was no reliable way to get goods from New Orleans to eastern cities.B.The cost of shipping goods by river to New Orleans continued to increase.C.Goods shipped from New Orleans' neighboring areas had a significant competitive advantage because of their lower transportation costs.D.The temperatures and humidity.6.Paragraph 4 supports the idea that the price of wheat more than doubled between 1845 and 1855 becauseA.the price of corn nearly doubled during that same period.B.demand for grain increased sharply outside the United States.C.farmers in the Northeast and Midwest began to specialize in cash crops.D.many farmers had borrowed heavily to purchase land and equipment for raising wheat.7.The word "transformed" in the passage (paragraph 5) is closest in meaning toA.dominated.B.changed.C.improved.D.created.8.The word "erected" in the passage (paragraph 5) is closest in meaning toA.looked for.B.lived on.C.preferred.D.built.9.Why does author point out that "Indian grass, Canada wild rye, and native big bluestem all grew higher than a person"(paragraph 5)?A.T o provide a reason why people from the eastern woodlands of the United States were impressed when they saw the prairie.B.To identify an obstacles to the development of the railroad lines fanning out from Chicago.C.To explain why the transformation of the prairies by commercial agriculture was so remarkable.D.T o provide evidence supporting the claim that the prairies had fertile, deep black soil.10.According to paragraph 5, the first settlers generally did not farm open prairie land becauseA.they could not plow it effectively with the tools that were available.B.prairie land was usually very expensive to buy.C.the soil along boundaries between the forest and the prairie was more fertile than the soil of the open prairie.D.the railroad lines had not yet reached the open prairie when the first settlersarrived.11.The word "surpluses" in the passage (paragraph 6) is closest in meaning toA.extra goodsmercial goodsC.unprocessed goodsD.transportable goods12.According to paragraph 8, prairie farmers changed the landscape by doing all of the following EXCEPT:A.Reducing annual fires.B.Dividing the land into large, regularly-shaped lots.C.Planting trees that eventually formed woodlots.D.Fencing off their farms.13. Look at the four squares [■] that indicate where the following sentence could be added to the passage. Where would the sentence best fit? The problems were not limited to routes of transport.The new railroad networks shifted the direction of western trade. ■【A】In 1840 most northwestern grain was shipped south down the Mississippi River to the bustling port of New Orleans. ■【B】But low water made steamboat travel hazardous in summer, and ice shut down traffic in winter. ■【C】Products such as lard, tallow, and cheese quickly spoiled if stored in New Orleans' hot and humid warehouses. ■【D】Increasingly, traffic from the Midwest flowed west to east, over the new rail lines. Chicago became the region's hub, linking the farms of the upper Midwest to NewYork and other eastern cities by more than 2,000 miles of track in 1855. Thus while the value of goods shipped by river to New Orleans continued to increase, the South's overall share of western trade dropped dramatically.14. Prose SummaryThe huge expansion of rail lines in Midwestern United States during the 1850s had major economic and environmental effects.A.Construction of new rail lines into the Midwest had been effectively stopped by the Appalachian Mountains, but by 1850 improved construction technology had made further advances possible.B.Rail lines to Chicago and on to the East made it easier to get Midwestern goods to distant markets, while growing demand encouraged crop specialization and led to higher crop prices.C.Because of the growing volume of traffic coming by rail from the Northeast and Midwest, the value of goods arriving in New Orleans for shipment to markets abroad increased dramatically.D.Access to rail lines combined with the development of more-efficient farming equipment allowed e fertile land of the open prairies to be used for large-scale commercial agriculture.E.Reduction of annual prairie fires allowed trees to reappear, and native grasses were replaced by a few commercially grown plants as previously unbroken grasslands were divided into large fenced fields.F.Native Americans had grown corn on the prairies for years but had not producedlarge surpluses because the varieties they planted had far poorer yields than those introduced by commercial farmers.答案:1.否定细节题:定位句By 1850 the United States possessed roughly 9,000 miles of railroad track;对应A 选项。

TPO33阅读详细答案

TPO33阅读详细答案

解析:词汇题。

答案A∙culminated in意为“到达…顶点,以…为终点”故选A: reached a high point with 迷惑选项∙ B logically followed from意为“逻辑上从…..跟随……”∙ C partly contributed to意为“部分的归因于…..”∙ D marked意为“标记,痕迹”解析:真实信息题。

答案A∙与原文信息The first farmers, who may have lived as long as 10,000 years ago, undoubtedly used simple techniques and still relied primarily on other forms of food production, such as hunting, foraging, or pastoralism. The realbreakthrough took place when farmers began to cultivate crops along thefloodplains of river systems相符迷惑选项∙ B 信息杂糅,原文信息为Many prehistorians believe that farming may have emerged in dependently in several different areas of the world when small communities, driven by increasing population and a decline in available food resources, began to plant seeds in the ground in an effort to guarantee their survival,原文核心描述为small communities began to plant seeds in theground而不是They were driven out of small communities∙ C 与原文相矛盾,原文信息为The advantage was that crops grown in such areas were not as dependent on rainfall and therefore produced a morereliable harvest即为农民受利于flood∙ D 与原文相矛盾,原文信息为thus enabling the farmer to cultivate a single plot of ground for many years without moving to a new location即农民是一次耕种一片地方解析:词汇题。

TPO阅读1-34汇总【含原文翻译解析答案】

TPO阅读1-34汇总【含原文翻译解析答案】

TPO阅读1-34汇总【含原文翻译解析答案】TPO1-34综合写作TPO 1 (1)1. 阅读部分 (1)2. 听力部分 (3)3. 范文赏析 (5)TPO 2 (7)1. 阅读部分 (7)2. 听力部分 (10)3. 范文赏析 (12)TPO 3 (14)1. 阅读部分 (14)2. 听力部分 (16)3. 范文赏析 (17)TPO4 (19)1. 阅读部分 (19)2. 听力部分 (20)3. 范文赏析 (22)TPO5 (24)1. 阅读部分 (24)2. 听力部分 (24)3. 范文赏析 (24)TPO6 (25)1. 阅读部分 (25)2. 听力部分 (25)3. 范文赏析 (25)TPO7 (26)1. 阅读部分 (26)2. 听力部分 (26)3. 范文赏析 (26) TPO8 (27)1. 阅读部分 (27)2. 听力部分 (27)3. 范文赏析 (27) TPO9 (28)1. 阅读部分 (28)2. 听力部分 (28)3. 范文赏析 (28) TPO10 (29)1. 阅读部分 (29)2. 听力部分 (29)3. 范文赏析 (29) TPO11 (30) 1. 阅读部分 (30) 3. 范文赏析 (30) TPO12 (31)1. 阅读部分 (31)2. 听力部分 (32)3. 范文赏析 (34) TPO13 (35)1. 阅读部分 (35)2. 听力部分 (36)3. 范文赏析 (38) TPO14 (39)1. 阅读部分 (39)2. 听力部分 (40)3. 范文赏析 (41) TPO15 (43) 1. 阅读部分 (43)3. 范文赏析 (45) TPO16 (47)1. 阅读部分 (47)2. 听力部分 (48)3. 范文赏析 (49) TPO17 (51)1. 阅读部分 (51)2. 听力部分 (52)3. 范文赏析 (54) TPO18 (55)1. 阅读部分 (55)2. 听力部分 (55)3. 范文赏析 (55) TPO19 (56)1. 阅读部分 (56)2. 听力部分 (56)3. 范文赏析 (56) TPO20 (57)1. 阅读部分 (57)2. 听力部分 (57)3. 范文赏析 (57) TPO21 (58)1. 阅读部分 (58)2. 听力部分 (58)3. 范文赏析 (58) TPO22 (59) 1. 阅读部分 (59) 3. 范文赏析 (59) TPO23 (60)2. 听力部分 (60)3. 范文赏析 (60) TPO24 (61)1. 阅读部分 (61)2. 听力部分 (61)3. 范文赏析 (61) TPO25 (62)1. 阅读部分 (62)2. 听力部分 (62)3. 范文赏析 (62) TPO26 (63)1. 阅读部分 (63)2. 听力部分 (63)3. 范文赏析 (63) TPO27 (64)1. 阅读部分 (64)2. 听力部分 (64)3. 范文赏析 (64) TPO28 (65)1. 阅读部分 (65)2. 听力部分 (65)3. 范文赏析 (65) TPO29 (66)1. 阅读部分 (66)2. 听力部分 (66)3. 范文赏析 (66) TPO30 (67)1. 阅读部分 (67)2. 听力部分 (67)3. 范文赏析 (67)TPO31 (68)1. 阅读部分 (68)2. 听力部分 (68)3. 范文赏析 (68)TPO32 (69)1. 阅读部分 (69)2. 听力部分 (70)3. 范文赏析 (70)TPO33 (71)1. 阅读部分 (71)3. 范文赏析 (71)TPO34 (72)1. 阅读部分 (72)2. 听力部分 (73)3. 范文赏析 (74)TPO 11. 阅读部分In the United States, employees typically work five days a week for eight hours each day. However, many employees want to work a four-day week and are willing to accept less pay in order to do so. A mandatory policy requiring companies to offer their employees the option of working a four-day workweek for four-fifths (80 percent) of their normal pay would benefit the economy as a whole as well as the individual companies and the employees who decided to take the option.在美国,职员一般执行的一周五天,每天八小时工作制。

托福备考托福阅读34套TPO样题+解析+译文TPO 33—3 灭绝事件

托福备考托福阅读34套TPO样题+解析+译文TPO 33—3  灭绝事件

托福考试 复习TPO 33—3 灭绝事件原文:【1】It was not until the Cambrian period, beginning about 600 million years ago, that a great proliferation of macroscopic species occurred on Earth and produced a fossil record that allows us to track the rise and fall of biodiversity. Since the Cambrian period, biodiversity has generally risen, but there have been some notable exceptions. Biodiversity collapsed dramatically during at least five periods because of mass extinctions around the globe. The five major mass extinctions receive most of the attention, but they are only one end of a spectrum of extinction events. Collectively, more species went extinct during smaller events that were less dramatic but more frequent. The best known of the five major extinction events, the one that saw the demise of the dinosaurs, is the Cretaceous-Tertiary extinction.【2】Starting about 280 million years ago, reptiles were the dominant large animals in terrestrial environments. In popular language this was the era “when dinosaurs ruled Earth,”when a wide variety of reptile species occupying many ecological niches. However, no group or species can maintain its dominance indefinitely, and when, after over 200 million years, the age of dinosaurs came to a dramatic end about 65 million years ago, mammals began to flourish, evolving from relatively few types of small terrestrial animals into the myriad of diverse species, including bats and whales, that we know today. Paleontologists la bel this point in Earth’s history as the end of the Cretaceous period and the beginning of the Tertiary period, often abbreviated as the K-T boundary. This time was also marked by changes in manyother types of organisms. Overall, about 38 percent of the families of marine animals were lost, with percentages much higher in some groups Ammonoid mollusks went from being very diverse and abundant to being extinct. An extremely abundant set of planktonic marine animals called foraminifera largely disappeared, although they rebounded later. Among plants, the K-T boundary saw a sharp but brief rise in the abundance of primitive vascular plants such as ferns, club mosses, horsetails, and conifers and other gymnosperms. The number of flowering plants (angiosperms) was reduced at this time, but they then began to increase dramatically.【3】What caused these changes? For many years scientists assumed that a cooling of the climate was responsible, with dinosaurs being particularly vulnerable because, like modern reptiles, they were ectothermic (dependent on environmental heat, or cold-blooded). It is now widely believed that at least some species of dinosaurs had a metabolic rate high enough for them to be endotherms (animals that maintain a relatively consistent body temperature by generating heat internally). Nevertheless, climatic explanations for the K-T extinction are not really challenged by the ideas that dinosaurs may have been endothermic, because even endotherms can be affected by a significant change in the climate.【4】Explanations for the K-T extinction were revolutionized in 1980 when a group of physical scientists led by Luis Alvarez proposed that 65 million years ago Earth was stuck by a 10-kilometer-wide meteorite traveling at 90,000 kilometers per hour. They believed that this impact generated a thick cloud of dust that enveloped Earth, shutting out much of the incoming solar radiation and reducing plantphotosynthesis to very low levels. Short-term effects might have included huge tidal waves and extensive fires. In other words, a series of events arising from a single cataclysmic event caused the massive extinctions. Initially, the meteorite theory was based on a single line of evidence. At locations around the globe, geologists had found an unusually high concentration of iridium in the layer of sedimentary rocks that was formed about 65 million years ago. Iridium is an element that is usually uncommon near Earth’s surface, but it is abundant in some meteorites. Therefore, Alvarez and his colleagues concludedthat it was likely that the iridium in sedimentary rocks deposited at the K-T boundary had originated in a giant meteorite or asteroid. Most scientist came to accept the meteorite theory after evidence came to light that a circular formation, 180 kilometers in diameter in diameter and centered on the north coast of the Yucatan Peninsula, was created by a meteorite impact about 65 million years ago.题目:1.The word "proliferation" in the passage (paragraph 1) is closest in meaning toA.decline.B.extinction.C.increase.D.migration.2.Paragraph 1 supports which of the following statements about life on Earth before the Cambrian period?A.Biodiversity levels were steady, as indicated by the fossil record.B.Levels of biodiversity could not be tracked.C.The most dramatic extinction episode occurred.D.Few microscopic species existed.3.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 dominance of dinosaurs came to an end 65 million years ago, at which time mammals began to flourish and diversify.B.Because no group of species can remain dominant forever, mammals became the dominant group when dinosaurs became extinct.C.After being the dominant group for more than 200 million years, the age of dinosaurs came to a dramatic end 65 million years ago.D.The diverse group of mammals that we know today, including bats and whales, evolved from small terrestrial forms that had been dominated by dinosaurs.4.According to paragraph 2, why are dinosaurs popularly said to have "ruled Earth" during the Cretaceous period?A.Dinosaurs were the only species of reptile that existed during the whole of the Cretaceous period.B.Dinosaurs won the battle for food resources over mammals during the Cretaceous period.C.Dinosaurs survived extinction during the Cretaceous period, whereas many otheranimal species did not.D.Dinosaurs were the physically and ecologically dominant animals during the Cretaceous period.5.According to paragraph 2, which of the following species initially increased in number at the K-T boundary?A.Dinosaurs.B.Foraminifera.C.Ferns.D.Ammonoid mollusks.6.Why does the author note that "even endotherms can be affected by a significant change in the climate"(paragraph 3)?A.T o argue that there was a significant climate at the time that endothermic dinosaurs became extinct.B.To argue that climate change caused some dinosaurs to evolve as endotherms.C.To support the view that at least some of the dinosaurs that became extinct were endotherms.D.T o defend climate change as possible explanation for the extinction of dinosaurs.7.The word "generated"(paragraph 4) in the passage is closest in meaning toA.collected.B.produced.C.spread.D.added.8.The word "extensive"(paragraph 4) in the passage is closest in meaning toA.widespread.B.sudden.C.numerous.D.subsequent.9.According to paragraph 4, all of the following contributed to the massive extinctions of the K-T period EXCEPT:A.tidal waves.B.fires.C.insufficient solar radiation.D.iridium.10.According to paragraph 4, which of the following statements explains the importance of the discovery of high levels of iridium rocks?A.It provided evidence that overexposure to solar radiation led to the K-T extinction.B.It showed that more than one cataclysmic event was responsible for the K-T extinction.C.It suggested that the cause of the K-T extinction may have been a meteorite striking Earth.D.It provided evidence that the K-T extinction occurred 65 million years ago.11.According to paragraph 4, which of the following is true about the Yucatan Peninsula?A.The circular formation there was caused by a meteorite impact 65 million yearsago.B.Sedimentary rocks from that area have the lowest iridium concentration of any rocks on Earth.C.There is evidence that a huge tidal wave occurred there 65 million years ago.D.Evidence found there challenged the meteorite impact theory.12.Which of the following can be inferred from paragraph 4 about the meteorite theory?A.The data originally presented as evidence for the theory were eventually rejected.B.Many scientists did not accept it when it was first proposed.C.It has not been widely accepted as an explanation for the K-T extinction.D.Alvarez subsequently revised it after a circular formation was found in the Yucatan Peninsula.13. Look at the four squares [■] that indicate where the following sentence could be added to the passage. Where would the sentence best fit? This focused on the chemical composition of ancient rocks.Explanations for the K-T extinction were revolutionized in 1980 when a group of physical scientists led by Luis Alvarez proposed that 65 million years ago Earth was stuck by a 10-kilometer-wide meteorite traveling at 90,000 kilometers per hour. They believed that this impact generated a thick cloud of dust that enveloped Earth, shutting out much of the incoming solar radiation and reducing plant photosynthesis to very low levels. Short-term effects might have included huge tidal waves and extensive fires. In other words, a series of events arising from a singlecataclysmic event caused the massive extinctions. ■【A】Initially, the meteorite theory was based on a single line of evidence. ■【B】At locations around the globe, geologists had found an unusually high concentration of iridium in the layer of sedimentary rocks that was formed about 65 million years ago. ■【C】Iridium is an element that is usually uncommon near Earth's surface, but it is abundant in some meteorites. ■【D】Therefore, Alvarez and his colleagues concluded that it was likely that the iridium in sedimentary rocks deposited at the K-T boundary had originated in a giant meteorite or asteroid. Most scientist came to accept the meteorite theory after evidence came to light that a circular formation, 180 kilometers in diameter in diameter and centered on the north coast of the Yucatan Peninsula, was created bya meteorite impact about 65 million years ago.14. Prose SummaryThe K-T extinction 65 million years ago is the best known of the five major extinction episodes since the Cambrian period.A.Collectively, the five major extinction episodes resulted in the elimination of a larger number of species than did all the minor extinction events.B.The K-T extinction eliminated the dinosaurs and ammonoid mollusks but was followed by the diversification of mammals and gymnospermous plants.C.An extreme cooling of the climate could not have caused the K-T extinction of dinosaurs, because, while most dinosaurs depended on environmental heat, some did not.D.The K-T extinction of the dinosaurs is the only mass extinction that has beenexplained by the impact of a meteorite.E.In 1980 Luis Alvarez proposed that the K-T extinction was caused by ecological disasters brought about by the impact of a meteorite striking Earth.F.A high concentration of iridium in sedimentary rocks at the K-T boundary and a large impact crater in the Yucatan Peninsula from 65 million years ago strongly support Alvarez' hypothesis答案:1.proliferation,繁殖,激增,对应C。

托福TPO阅读33 双语文本+答案解析

托福TPO阅读33 双语文本+答案解析

小编推荐:查看托福口语TPO1-33文本+MP3,请点击:TPO口语1-34查看托福写作TPO1-25文本大全,请点击:TPO写作1-25查看托福听力TPO1-29原文+题目+MP3音频下载,请点击:TPO听力1-30托福TPO阅读33 双语文本+答案解析查看托福阅读TPO1-32阅读原文+题目+答案,请点击:TPO阅读1-32The First CivilizationsEvidence suggests that an important stimulus behind the rise of early civilizations was the development of settled agriculture, which unleashed a series of changes in the organization of human communities that culminated in the rise of large ancient empires.证据显示,早期文明兴起的一个重要刺激因素就是定居农业的发展。

它导致了人类群落的组织结构出现一系列变更,在古代大型帝国的兴起时达到了顶峰。

The exact time and place that crops were first cultivated successfully is uncertain. Many prehistorians believe that farming may have emerged independently in several different areas of the world when small communities, driven by increasing population and a decline in available food resources, began to plant seeds in the ground in an effort to guarantee their survival. The first farmers, who may have lived as long as 10,000 years ago, undoubtedly used simple techniques and still relied primarily on other forms of food production, such as hunting, foraging, or pastoralism. The real breakthrough took place when farmers began to cultivate crops along the floodplains of river systems. The advantage was that crops grown in such areas were not as dependent on rainfall and therefore produced a more reliable harvest. An additional benefit was that the sediment carried by the river waters deposited nutrients in the soil, thus enabling the farmer to cultivate a single plot of ground for many years without moving to a new location. Thus, the first truly sedentary (that is, non-migratory) societies were born. As time went on, such communities gradually learned how to direct the flow of water to enhance the productive capacity of the land, while the introduction of the iron plow eventually led to the cultivation of heavy soils not previously susceptible to agriculture.庄稼究竟是何时何地被首次成功开垦种植还不得而知。

托福阅读真题及答案 PASSAGE 2

托福阅读真题及答案 PASSAGE 2

托福阅读真题及答案 PASSAGE 2选择出guo学习的人数越来越多,参加无疑是进入国外大学的一块敲门砖。

以下是网的关于托福阅读真题及答案:PASSAGE 2,供大家练习备考。

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 pounds and is constantly modifying the face of the Earth.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 agentof continental erosion: rain. Precipitated onto the ground, the water trickles down to form brooks, streams, and rivers, constituting what are called the hydrographic work. This immense polarized work channels the water toward a single receptacle: an ocean. 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 though the cycle is not random but is a measure of the relative sizeof the various reservoirs. If we define residence time asthe average time for a water molecule to pass through oneof 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 yearsin the ocean. This last figure shows the importance of the ocean as the principal reservoir of the hydrosphere but also the rapidity of water 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 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.1. The word "modifying" in line 4 is closest in meaning to(A) changing(B) traveling(C) describing(D) destroying2. The word "which" in line 5 refers to(A) clouds(B) oceans(C) continents(D) pounds3. Aording to the passage , clouds are primarily formed by water(A) precipitating onto the ground(B) changing from a solid to a liquid state(C) evaporating from the oceans(D) being carried by wind4. The passage suggests that the purpose of the "hydrographic work" (line 8) is to(A) determine the size of molecules of water(B) prevent soil erosion caused by flooding(C) move water from the Earth's surface to the oceans(D) regulate the rate of water flow from streams and rivers5. What determines the rate at which a molecule of water moves through the cycle, as discussed in the third paragraph?(A) The potential energy contained in water(B) The effects of atmospheric pressure on chemical pounds(C) The amounts of rainfall that fall on the continents(D) The relative size of the water storage areas6. The word "rapidity" in line 19 is closest in meaning to(A) significance(B) method(C) swiftness(D) reliability7. The word "they" in line 24 refers to(A) insoluble ions(B) soluble ions(C) soils(D) continents8. All of the following are example of soluble ions EXCEPT(A) magnesium(B) iron(C) potassium(D) calcium9. The word "efficiency" in line 27 is closest in meaning to(A) relationship(B) growth(C) influence(D) effectiveness。

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为了帮助大家高效备考托福,为大家带来托福TPO33阅读Passage2原文文本+题目+答案解析,希望对大家备考有所帮助。

Railroads and Commercial Agriculture in Nineteenth-Century United States By 1850 the United States possessed roughly 9,000 miles of railroad track;then years later it had over 30,000 miles,more than the rest of the world combined.Much of the new construction during the 1850s occurred west of the Appalachian Mountains–over 2,000 miles in the states of Ohio and Illinois alone. The effect of the new railroad lines rippled outward through the economy.Farmers along the tracks began to specialize in corps that they could market in distant locations.With their profits they purchased manufactured goods that earlier they might have made at home.Before the railroad reached Tennessee,the state produced about 25,000 bushels(or 640 tons)of wheat,which sold for less than 50 cents a bushel.Once the railroad came,farmers in the same counties grew 400,000 bushels(over 10,000 tons)and sold their crop at a dollar a bushel. The new railroad networks shifted the direction of western trade.In 1840 most northwestern grain was shipped south down the Mississippi River to the bustling port of New Orleans.But low water made steamboat travel hazardous in summer,and ice shut down traffic in winter.Products such as lard,tallow,and cheese quickly spoiled if stored in New Orleans’hot and humid warehouses.Increasingly,traffic from the Midwest flowed west to east,over the new rail lines.Chicago became the region’s hub,linking the farms of the upper Midwest to New York and other eastern cities by more than 2,000 miles of track in 1855.Thus while the value of goods shipped by river to New Orleans continued to increase,the South’s overall share of western trade dropped dramatically. A sharp rise in demand for grain abroad also encouraged farmers in the Northeast and Midwest to become more commercially oriented.Wheat,which in 1845 commanded$1.08 a bushel in New York City,fetched$2.46 in 1855;in similar fashion the price of corn nearly doubled.Farmers responded by specializing in cash crops,borrowing to purchase more land,and investing in equipment to increase productivity. As railroad lines fanned out from Chicago,farmers began to acquire open prairie land in Illinois and then Iowa,putting the fertile,deep black soil into production. Commercial agriculture transformed this remarkable treeless environment.To settlers accustomed to eastern woodlands,the thousands of square miles of tall grass were an awesome sight.Indian grass,Canada wild rye,and native big bluestem all grew higher than a person.Because eastern plows could not penetrate the densely tangled roots of prairie grass,the earliest settlers erected farms along the boundary separating the forest from the prairie.In 1837,however,John Deere patented a sharp-cutting steel plow that sliced through the sod without soil sticking to the blade.Cyrus McCormick refined a mechanical reaper that harvested fourteen times more wheat with the same amount of labor.By the 1850s McCormick was selling 1,000 reapers a year and could not keep up with demand,while Deere turned out 10,000 plows annually. The new commercial farming fundamentally altered the Midwestern landscape and the environment.Native Americans had grown corn in the region for years,but never in such large fields as did later settlers who became farmers,whose surpluses were shipped east.Prairie farmers also introduced new crops that were not part of the earlier ecological system,notably wheat,along with fruits and vegetables. Native grasses were replaced by a small number of plants cultivated as commodities.Corn had the best yields,but it was primarily used to feed livestock.Because bread played a key role in the American and European diet,wheat became the major cash crop.Tame grasses replaced native grasses in pastures for making hay. Western farmers altered the landscape by reducing the annual fires that had kept the prairie free from trees.In the absence of these fires,trees reappeared on land not in cultivation and,if undisturbed,eventually formed woodlots.The earlier unbroken landscape gave way to independent farms,each fenced off in a precise checkerboard pattern.It was an artificial ecosystem of animals,woodlots,and crops,whose large,uniform layout made western farms more efficient than the more-irregular farms in the East. 译文:十九世纪美国的铁路和商品农业 在1850年之前美国有约9,000英里铁轨,几年之后铁轨的长度增加到30,000多英里,比世界上其他地方的总和还要多。

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