TOEFL阅读系列3-3
tpo32三篇托福阅读TOEFL原文译文题目答案译文背景知识
tpo32三篇托福阅读TOEFL原文译文题目答案译文背景知识阅读-1 (2)原文 (2)译文 (5)题目 (7)答案 (16)背景知识 (16)阅读-2 (25)原文 (25)译文 (28)题目 (31)答案 (40)背景知识 (41)阅读-3 (49)原文 (49)译文 (53)题目 (55)答案 (63)背景知识 (64)阅读-1原文Plant Colonization①Colonization is one way in which plants can change the ecology of a site.Colonization is a process with two components:invasion and survival.The rate at which a site is colonized by plants depends on both the rate at which individual organisms(seeds,spores,immature or mature individuals)arrive at the site and their success at becoming established and surviving.Success in colonization depends to a great extent on there being a site available for colonization–a safe site where disturbance by fire or by cutting down of trees has either removed competing species or reduced levels of competition and other negative interactions to a level at which the invading species can become established.For a given rate of invasion,colonization of a moist,fertile site is likely to be much more rapid than that of a dry, infertile site because of poor survival on the latter.A fertile,plowed field is rapidly invaded by a large variety of weeds,whereas a neighboring construction site from which the soil has been compacted or removed to expose a coarse,infertile parent material may remain virtually free of vegetation for many months or even years despite receiving the same input of seeds as the plowed field.②Both the rate of invasion and the rate of extinction vary greatly among different plant species.Pioneer species-those that occur only in the earliest stages of colonization-tend to have high rates of invasion because they produce very large numbers of reproductive propagules(seeds,spores,and so on)and because they have an efficient means of dispersal(normally,wind).③If colonizers produce short-lived reproductive propagules,they must produce very large numbers unless they have an efficient means of dispersal to suitable new habitats.Many plants depend on wind for dispersal and produce abundant quantities of small,relatively short-lived seeds to compensate for the fact that wind is not always a reliable means If reaching the appropriate type of habitat.Alternative strategies have evolved in some plants,such as those that produce fewer but larger seeds that are dispersed to suitable sites by birds or small mammals or those that produce long-lived seeds.Many forest plants seem to exhibit the latter adaptation,and viable seeds of pioneer species can be found in large numbers on some forest floors. For example,as many as1,125viable seeds per square meter were found in a100-year-old Douglas fir/western hemlock forest in coastal British Columbia.Nearly all the seeds that had germinated from this seed bank were from pioneer species.The rapid colonization of such sites after disturbance is undoubtedly in part a reflection of the largeseed band on the forest floor.④An adaptation that is well developed in colonizing species is a high degree of variation in germination(the beginning of a seed’s growth). Seeds of a given species exhibit a wide range of germination dates, increasing the probability that at least some of the seeds will germinate during a period of favorable environmental conditions.This is particularly important for species that colonize an environment where there is no existing vegetation to ameliorate climatic extremes and in which there may be great climatic diversity.⑤Species succession in plant communities,i.e.,the temporal sequence of appearance and disappearance of species is dependent on events occurring at different stages in the life history of a species. Variation in rates of invasion and growth plays an important role in determining patterns of succession,especially secondary succession. The species that are first to colonize a site are those that produce abundant seed that is distributed successfully to new sites.Such species generally grow rapidly and quickly dominate new sites, excluding other species with lower invasion and growth rates.The first community that occupies a disturbed area therefore may be composed of specie with the highest rate of invasion,whereas the community of the subsequent stage may consist of plants with similar survival ratesbut lower invasion rates.译文植物定居①定居是植物改变一个地点生态环境的一种方式。
tpo36三篇托福阅读TOEFL原文译文题目答案译文背景知识
tpo36三篇托福阅读TOEFL原文译文题目答案译文背景知识阅读-1 (2)原文 (2)译文 (3)题目 (5)答案 (10)背景知识 (11)阅读-2 (12)原文 (12)译文 (14)题目 (15)答案 (20)背景知识 (20)阅读-3 (24)原文 (24)译文 (25)题目 (27)答案 (32)背景知识 (33)阅读-1原文Soil Formation①Living organisms play an essential role in soil formation. The numerous plants and animals living in the soil release minerals from the parent material from which soil is formed, supply organic matter, aid in the translocation (movement) and aeration of the soil, and help protect the soil from erosion. The types of organisms growing or living in the soil greatly influence the soil's physical and chemical characteristics. In fact, for mature soils in many parts of the world, the predominant type of natural vegetation is considered the most important direct influence on soil characteristics. For this reason, a soil scientist can tell a great deal about the attributes of the soil in any given area simply from knowing what kind of flora the soil supports. Thus prairies and tundra regions, which have characteristic vegetations, also have characteristic soils.②The quantity and total weight of soil flora generally exceed that of soil fauna. By far the most numerous and smallest of the plants living in soil are bacteria. Under favorable conditions, a million or more of these tiny, single-celled plants can inhabit each cubic centimeter of soil. It is the bacteria, more than any other organisms, that enable rock or other parent material to undergo the gradual transformation to soil. Some bacteria produce organic acids that directly attack parent material, breaking it down and releasing plant nutrients. Others decompose organic litter (debris) to form humus (nutrient-rich organic matter). A third group of bacteria inhabits the root systems of plants called legumes. These include many important agricultural crops, such as alfalfa, clover, soybeans, peas, and peanuts. The bacteria that legumes host within their root nodules (small swellings on the root) change nitrogen gas from the atmosphere into nitrogen compounds that plants are able to metabolize, a process, known as nitrogen fixation, that makes the soil more fertile. Other microscopic plants also are important in soil development. For example, in highly acidic soils where few bacteria can survive, fungi frequently become the chief decomposers of organic matter.③More complex forms of vegetation play several vital roles with respect to the soil. Trees, grass, and other large plants supply the bulk of the soil's humus. The minerals released as these plants decompose on the surface constitute an important nutrient source for succeeding generations of plants as well as for other soil organisms. In addition, trees can extend their roots deep within the soil and bring up nutrients from far below the surface. These nutrients eventually enrich the surface soil when the tree drops its leaves or when it dies and decomposes. Finally, trees perform the vital function of slowing water runoff and holding the soil in place with their root systems, thus combating erosion. The increased erosion that often accompanies agricultural use of sloping land is principally caused by the removal of its protective cover of natural vegetation.④Animals also influence soil composition. The faunal counterparts of bacteria are protozoa. These single-celled organisms are the most numerous representatives of the animal kingdom, and, like bacteria, a million or more can sometimes inhabit each cubic centimeter of soil. Protozoa feed on organic matter and hasten its decomposition. Among other soil-dwelling animals, the earthworm is probably the most important. Under exceptionally favorable conditions, up to a million earthworms (with a total body weight exceeding 450 kilograms) may inhabit an acre of soil. Earthworms ingest large quantities of soil, chemically alter it, and excrete it as organic matter called casts. The casts form a high-quality natural fertilizer. In addition, earthworms mix of soil both vertically and horizontally, improving aeration and drainage.⑤Insects such as ants and termites also can be exceedingly numerous under favorable climatic and soil conditions. In addition, mammals such as moles, field mice, gophers, and prairie dogs sometimes are present in sufficient numbers to have significant impact on the soil. These animals primarily work the soil mechanically. As a result, the soil is aerated broken up, fertilized, and brought to the surface, hastening soil development.译文土壤形成①活生物体在土壤形成中起着重要作用。
托福阅读TOEFL三篇tpo66原文译文题目答案背景知识
托福阅读TOEFL三篇tpo66原文译文题目答案背景知识阅读-1 (2)原文 (2)译文 (6)题目 (9)答案 (16)背景知识 (17)阅读-2 (23)原文 (23)译文 (27)题目 (30)答案 (38)背景知识 (39)阅读-3 (41)原文 (41)译文 (44)题目 (47)答案 (54)背景知识 (56)阅读-1原文The Actor and the Audience①Actors,even when they are well rehearsed,can never fully anticipate how well they will perform before an actual audience.The actor who has been brilliant in rehearsal can crumble before an audience and completely lose the“edge”of his or her performance in the face of stage fright and apprehension.The presence of an audience can affect performance in other ways as well.Or—and this is more likely —an actor who seemed fairly unexciting at rehearsal can suddenly take fire and dazzle the audience with unexpected energy,subtlety,and depth.One celebrated example of this phenomenon was achieved by Lee J.Cobb in the original production of Arthur Miller’s Death of a Salesman,in which Cobb had the title role.Roles rehearsed in all solemnity can suddenly turn comical in performance;conversely,roles developed for comic potential in rehearsal may be received soberly by an audience and lose their comedic aspect entirely.②Sudden and dramatic change,however,is not the norm as the performance phase replaces rehearsal:most actors cross over from final dress rehearsal to opening night with only the slightest shift;indeed,this is generally thought to be the goal of a disciplined and professional rehearsal schedule.Holding back until opening night,the once-popular acting practice of restraining emotional display until opening night,is universally disavowed today,and opening night recklessness is viewed as a sure sign of the amateur,who relies primarily on guts and adrenaline to get through the performance.Deliberate revision of a role in performance,in response to the first waves of laughter or applause,is similarly frowned upon in all but the most inartistic of theaters today.③Nevertheless,a fundamental shift does occur in the actor’s awareness between rehearsal and performance,and this cannot and should not be denied;indeed,it is essential to the creation of theater art.This shift is set up by an elementary feedback:the actor is inevitably aware,with at least a portion of his or her mind,of the audience’s reaction to his or her own performance and that of the other players;there isalways,in any acting performance,a subtle adjustment to the audience that sees it.The outward manifestations of this adjustment are usually all but imperceptible:the split-second hold for a laugh to die down,the slight special projection of a certain line to make sure that it reaches the back row,the quick turn of a head to make a characterization or plot transition extra clear.④In addition,the best actors consistently radiate a quality known to the theater world as presence.It is a quality difficult to describe,but it has the effect of making both the character whom the actor portrays and the self of the actor who represents that character especially vibrant and in the present for the audience;it is the quality of an actor who takes the stage and acknowledges,in some inexplicable yet indelible manner,that he or she is there to be seen.Performance is not a one-way statement given from the stage to the house;it is a two-way participatory communication between the actors and the audience members in which the former employ text and movement and the latter employ applause,laughter, silence,and attention.⑤Even when the audience is silent and invisible—and,owing to the brightness of the stage lights,the audience is frequently invisible to the actor—the performer feels its presence.There is nothing extrasensory about this:the absence of sound is itself a signal,for when several hundred people sit without shuffling,coughing,or muttering,their silence betokens a level of attention for which the actor customarily ughter,gasps,sighs,and applause similarly feed back into the actor’s consciousness—and unconsciousness—and spur(or sometimes,alas,distract)the actor’s efforts.The veteran actor can determine quickly how to ride the crest of audience laughter and how to hold the line just long enough that it will pierce the lingering chuckles but not be overridden by them;he or she also knows how to vary the pace and/or redouble his or her energy when sensing restlessness or boredom on the other side of the curtain line. Performance technique,or the art of reading an audience,is more instinctual than learned.The timing it requires is of such complexity that no actor could master it rationally;he or she can develop it only out of experience.译文演员和观众①演员，即使是经过充分排练，也无法完全预测他们在真实观众面前的表现。
TOEFL阅读历年考题分类：题材篇(三)
TOEFL阅读历年考题分类：题材篇（三）（三）自然科学：1.植物学，微生物2.动物学3.生理学4.地质学，地理学，天文学，气象学5.考古学，人类学6.物理，化学，医药，环境1.植物学S/P1树叶为何变颜色82/11海藻83/1地衣S1/P12386/1植物演化86/5藤蔓植物，86/10地衣S1/P788/1树的防御机理S1/P1788/5植物形成层和树皮结构S1/P99S/P69植物的根90/8浮游生物P3291/8植物学P54普样题192/8树的重要性P71P89/植物拟态的性质和作用P138/沙漠植物的生存95/10植物内部运水的机理96/1植物的防御机理北美题96/5兰花96/10一种野草和牛的传说98/5赤扬和森林环境的关系99/8菌类和植物的区别及破坏性和用途2.动物学81/11鸟类适应的演化82/1蝙蝠的生物声纳83/5蚊子利用水产卵83/5有机椎动物和无脊椎动物中ALLEOMIMETIC的作用S1/P95 83/8濑鱼S1/P6283/11海獭84/5响尾蛇的响声84/11旋木雀S1/P7885/5蜜蜂酿蜜S1/P8686/1牛胃S1/P6786/3蜜蜂结构适宜社会化S1/P7586/8恐龙绝迹的解释87/1鸟类学87/5动物为何不生轮子S1/P1687/8北美野牛S1/P10387/10猴子尾巴88/1蜜蜂意识测试S1/P20S/P24沼泽中的动物S1/P24S/P37蜜蜂的社会结构S1/P37S/P39美洲鳄鱼交配后S1/P39S/P52莺科鸣禽划分树上食物S1/P52S/P56食物网S1/P56S/P93考拉S1/P9388/5北极熊S1/P98S/P109灵长类动物的社会行为S1/P109S/P112猿S1/P11288/10鲸鱼S1/P13389/1树懒的习性P289/5美国蝗虫灾害P989/10河狸P1890/1马的进化P2290/8浮游生物P3291/5河狸的特征和习性P4892/1信鸽训练P6192/5病毒P67P80/细菌的特性P90/海葵P98/昆虫的伪装P105/候鸟飞行的高度和速度P116/动物导航P122/血液温度和动物分类P141海洋与生命P142黑猩猩的社会化生活P147贫齿类动物犰犹ARMADILLOS普样2候鸟迁徙的原因S1/P121普样3海葵95/12海洋生物多样性96/1海参96/8研究乌鸦的困难96/10猎狗的嗅觉物质97/1沙漠动物适应97/5鸟儿群居的原因97/10交喙鸟的鸟嘴结构98/1有机物如何对入侵者作出反应98/8动物行为认识99/10爬行动物和鸟类飞行的发展3．生理学99/8临床营养学的发展阶段84/5人类疾病的两个原理99/5有机椎动物的神经系统85/11大脑和中央神经系统的起源83/8大脑意识反应的听觉测试S/P53婴儿大脑成熟和感情发育S1/P53P118/新陈代谢中盐的演化P110/睡眠的阶段86/10睡眠的功能和分类S1/P11S/P136两类睡眠S1/P136 82/1休眠P101/人类肌肉解剖和动作P96/生物与电90/5荷尔蒙P284．地质学，地理学，天文学，气象学2000/1土壤结构的确定方法S/P107土壤的类型99/101994/7流星袭击木星90/10彗星P3999/5极光的形成和表象99/1火成岩98/10地球表面水S/P35大气中的水98/8地球表面的陨石P133/陨石分类S/P4陨石坑98/5宇宙中氦何时形成97/10星系P148/星的分类系统S/P49星的亮度97/1宇宙星体形状95/12地球板块运动96/12地球板块结构理论对地质学的贡献P94/地球板块结构理论S/P58地球板块96/10地震波与地球内部结构研究82/11地球冰河期S1/P12596/1飓风预报86/5气象学91/5飓风P4587/1飓风95/8海底探险普样3海底探索普样4太阳结构P56P82/太阳的演化89/5太阳发光和热P892/10地球和宇宙P7588/10宇宙的理解91/8加拿大省BRITISH COLUMBIA P50 87/8大峡谷的形成S1/P10495/12美国大盆地P145/阿拉斯加半岛S/P76气候决定动植物的分布P42/冰山的特征和起源S/P125冰河期82/8田那西洲东部地下湖82/11地球冰河期P121/洞冰起源96/5火山冰洞降雪的重要性5．考古学，人类学98/8骨化石比骨骼重的原因NA98/1化石足迹分析97/12化石保存条件NA95/10鱼龙胚胎化石96/8历史考古学96/1人类右手为主的考古学证据NAP99/左右手的形成P92/考古学和人类历史P86/考古学的工作方法6．物理，化学，医药，环境91/8降雨的机理普样195/10植物内部运水的机理96/1植物防御的机理北美NA97/5猫降落的机理98/8燃烧的解释98/8雪花的形成北美99/5极光的形成和表象97/8钢丝篱笆97/8一种新型显微镜97/12空气污染物定义98/8人类行为对地球生态系的影响98/1玻璃91/5统计学的发展和用途普样292/5海水盐度普样2？/制陶普样3 95/8戏剧起源95/10钢琴的历史发展95/12无声电影的音乐98/1爵士乐和其它音乐的区别95/12海洋生物多样性96/1N冰箱的发展北美96/5美国西部蒸汽船发动机97/5直接雕塑。
托福TPO3阅读Passage3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Passage3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Passage3原文文本： The Long-Term Stability of Ecosystems Plant communities assemble themselves flexibly, and their particular structure depends on the specific history of the area. Ecologists use the term “succession” to refer to the changes that happen in plant communities and ecosystems over time. The first community in a succession is called a pioneer community, while the long-lived community at the end of succession is called a climax community. Pioneer and successional plant communities are said to change over periods from 1 to 500 years. These changes—in plant numbers and the mix of species—are cumulative. Climax communities themselves change but over periods of time greater than about 500 years. An ecologist who studies a pond today may well find it relatively unchanged in a year’s time. Individual fish may be replaced, but the number of fish will tend to be the same from one year to the next. We can say that the properties of an ecosystem are more stable than the individual organisms that compose the ecosystem. At one time, ecologists believed that species diversity made ecosystems stable. They believed that the greater the diversity the more stable the ecosystem. Support for this idea came from the observation that long-lasting climax communities usually have more complex food webs and more species diversity than pioneer communities. Ecologists concluded that the apparent stability of climax ecosystems depended on their complexity. To take an extreme example, farmlands dominated by a single crop are so unstable that one year of bad weather or the invasion of a single pest can destroy the entire crop. In contrast, a complex climax community, such as a temperate forest, will tolerate considerable damage from weather to pests. The question of ecosystem stability is complicated, however. The first problem is that ecologists do not all agree what “stability” means. Stability can be defined as simply lack of change. In that case, the climax community would be considered the most stable, since, by definition, it changes the least over time. Alternatively, stability can be defined as the speed with which an ecosystem returns to a particular form following a major disturbance, such as a fire. This kind of stability is also called resilience. In that case, climax communities would be the most fragile and the least stable, since they can require hundreds of years to return to the climax state. Even the kind of stability defined as simple lack of change is not always associated with maximum diversity. At least in temperate zones, maximum diversity is often found in mid-successional stages, not in the climax community. Once a redwoodforest matures, for example, the kinds of species and the number of individuals growing on the forest floor are reduced. In general, diversity, by itself, does not ensure stability. Mathematical models of ecosystems likewise suggest that diversity does not guarantee ecosystem stability—just the opposite, in fact. A more complicated system is, in general, more likely than a simple system to break down.A fifteen-speed racing bicycle is more likely to break down than a child’s tricycle. Ecologists are especially interested to know what factors contribute to the resilience of communities because climax communities all over the world are being severely damaged or destroyed by human activities. The destruction caused by the volcanic explosion of Mount St. Helens, in the northwestern United States, for example, pales in comparison to the destruction caused by humans. We need to know what aspects of a community are most important to the community’s resistance to destruction, as well as its recovery. Many ecologists now think that the relative long-term stability of climax communities comes not from diversity but from the “patchiness” of the environment, an environment that varies from place to place supports more kinds of organisms than an environment that is uniform. A local population that goes extinct is quickly replaced by immigrants from an adjacent community. Even if the new population is of a different species, it can approximately fill the niche vacated by the extinct population and keep the food web intact. ▉托福TPO3阅读Passage3题目： Question 1 of 14 The word “particular ” in the passage is closest in meaning to A. natural. B. final. C. specific. D. complex. Question 2 of 14 According to paragraph 1, which of the following is NOT true of climax communities? A. They occur at the end of a succession..。
TOEFL托福阅读理解真题
TOEFL托福阅读理解真题为了让大家更好的预备托福考试，我给大家整理一些托福阅读真题，下面我就和大家共享，来观赏一下吧。
托福阅读真题1It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time — a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died,mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affection even organisms not living in the oceans. Such a change would probably lead to a mass extinction.One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. This periodic extinction might be due to intersection of the Earths orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.1. The word it in line 3 refers to(A) environment(B) species(C) extinction(D) 99 percent2. The word ultimately in line 8 is closest in meaning to(A) exceptionally(B) dramatically(C) eventually(D) unfortunately3. What does the author say in paragraph 1 regarding most species in Earths history(A) They have remained basically unchanged from their original forms.(B) They have been able to adapt to ecological changes.(C) They have caused rapid change in the environment.(D) They are no longer in existence.4. Which of the following is NOT mentioned in paragraph 1 as resulting from rapid ecologicalchange?(A) Temperature changes(B) Availability of food resources(C) Introduction of new species(D) Competition among species5. The word demise in line 12 is closest in meaning to(A) change(B) recovery(C) help(D) death6. Why is plankton mentioned in line 17?(A) To demonstrate the interdependence of different species.(B) To emphasize the importance of food resources in preventing mass extinction.(C) To illustrate a comparison between organisms that live on the land and those that live in theocean.(D) To point out that certain species could never become extinct.7. According to paragraph 2, evidence from fossils suggests that(A) Extinction of species has occurred from time to time throughout Earths history.(B) Extinctions on Earth have generally been massive(C) There has been only one mass extinction in Earths history.(D) Dinosaurs became extinct much earlier than scientists originally believed.8. The word finding in line 20 is closest in meaning to(A) published information(B) research method(C) ongoing experiment(D) scientific discovery9. Which of the following can be inferred about the theory mentioned in Line 21-23?(A) Many scientists could be expected to disagree with it.(B) Evidence to support the theory has recently been found.(C) The theory is no longer seriously considered.(D) Most scientists believe the theory to be accurate.10. In paragraph 3, the author makes which of the following statements about a species survival?(A) It reflects the interrelationship of many species.(B) It may depend on chance events.(C) It does not vary greatly from species to species(D) It is associated with astronomical conditions.11. According to the passage , it is believed that the largest extinction of a species occurred(A) 26 million years ago(B) 65 million years ago(C) 225 million years ago(D) 250 million years agoPASSAGE 77 BCDCD AADAB C托福阅读真题2Archaeological discoveries have led some scholars to believe that the first Mesopotamian inventors of writing may have been a people the later Babylonians called Subarians. According to tradition, they came from the north and moved into Uruk in the south. By about 3100 B.C.,they were apparently subjugated in southern Mesopotamia by the Sumerians, whose name became synonymous with the region immediately north of the Persian Gulf, in the fertile lower valleys of the Tigris and Euphrates. Here the Sumerians were already well established by the year 3000 B.C. They had invented bronze, an alloy that could be cast in molds, out of which they made tools and weapons. They lived in cities, and they had begun to acquire and use capital. Perhaps most important, the Sumerians adapted writing (probably from the Subarians) into a flexible tool of communication.Archaeologists have known about the Sumerians for over 150 years. Archaeologists working at Nineveh in northern Mesopotamia in the mid-nineteenth century found many inscribed clay tablets. Some they could decipher because the language was a Semitic one (Akkadian), on which scholars had already been working for a generation. But other tablets were inscribed in another language that was not Semitic and previously unknown. Because these inscriptions made reference to the king of Sumer and Akkad, a scholar suggested that the new language be called Sumerian.But it was not until the 1890s that archaeologists excavating in city-states well to the south of Nineveh found many thousands of tablets inscribed in Sumerian only. Because the Akkadians thought of Sumerian as a classical language (as ancient Greek and Latin are considered today),they taught it to educated persons and they inscribed vocabulary, translation exercises, and other study aids on tablets. Working from known Akkadian to previously unknown Sumerian, scholars since the 1890s have learned how to read the Sumerian language moderately well. Vast quantities of tablets in Sumerian have been unearthed during the intervening years from numerous sites.1. According to the passage , the inventors of written language in Mesopotamia were probablythe(A) Babylonians(B) Subarians(C) Akkadians(D) Sumerians2. The word subjugated in line 4 is closest in meaning to(A) distinguished(B) segregated(C) concentrated(D) conquered3. The phrase synonymous with in line 5 is closest in meaning to(A) equivalent to(B) important for(C) respected in(D) familiar with4. According to the passage , by the year 3000 B.C. the Sumerians had already done all of thefollowing EXCEPT:(A) They had abandoned the area north of the Persian Gulf.(B) They had established themselves in cities.(C) They had started to communicate through(D) They had created bronze tools and weapons.5. The word some in line 14 refers to(A) Archaeologists(B) Sumerians(C) years(D) clay tablets6. Which of the following can be inferred from the passage concerning the Sumerians?(A) They were descendants of the Persians.(B) They were the first people to cultivate the valley of the Tigris.(C) They were accomplished musicians.(D) They had the beginnings of an economy.7. According to the passage , when did archaeologists begin to be able to understand tabletsinscribed in Sumerian?(A) in the early nineteenth century(B) more than 150 years ago(C) after the 1890s(D) in the mid-eighteenth century8. According to the passage , in what way did the Sumerian language resemble ancient Greek andLatin?(A) It was invented in Mesopotamia.(B) It became well established around 3000 B.C.(C) It became a classical language.(D) It was used exclusively for business transactions.9. The word excavating in line 19 is closest in meaning to(A) living(B) digging(C) assembling(D) building10. According to the passage , how did archaeologists learn to read the Sumerian language?(A) by translating the work of the Subarians(B) by using their knowledge of spoken Semitic languages(C) by comparing Sumerian to other classical languages(D) by using their knowledge of AkkadianPASSAGE 78 BDAAD DCCBD托福阅读真题3Some animal behaviorists argue that certain animals can remember past events, anticipate future ones, make plans and choices, and coordinate activities within a group. These scientists, however, are cautious about the extent to which animals can be credited with conscious processing.Explanations of animal behavior that leave out any sort of consciousness at all and ascribe actions entirely to instinct leave many questions unanswered. One example of such unexplained behavior: honeybees communicate the sources of nectar to one another by doing a dance in a figure-eight pattern. The orientation of the dance conveys the position of the food relative to the suns position in the sky, and the speed of the dance tells how far the food source is from the hive. Most researchers assume that the ability to perform and encode the dance is innate and shows no special intelligence. But in one study, when experimenters kept changing the site of the food source, each time moving the food 25 percent farther from the previous site, foraging honeybees began to anticipate where the food source would appear next. When the researchers arrived at the new location, they would find the bees circling the spot, waiting for their food. No one has yet explained how bees, whose brains weigh four ten-thousandths of anounce, could have inferred the location of the new site.Other behaviors that may indicate some cognition include tool use. Many animals, like the otter who uses a stone to crack mussel shells, are capable of using objects in the natural environment as rudimentary tools. One researcher has found that mother chimpanzees occasionally show their young how to use tools to open hard nuts. In one study, chimpanzees compared two pairs of food wells containing chocolate chips. One pair might contain, say, five chips and three chips, the other four chips and three chips. Allowed to choose which pair they wanted, the chimpanzees almost always chose the one with the higher total, showing some sort of summing ability. Other chimpanzees have learned to use numerals to label quantities of items and do simple sums.1. What does the passage mainly discuss?(A) The role of instinct in animal behavior(B) Observations that suggest consciousness in animal behavior(C) The use of food in studies of animal behavior(D) Differences between the behavior of animals in their natural environments and in laboratoryexperiments.2. Which of the following is NOT discussed as an ability animals are thought to have?(A) Selecting among choices(B) Anticipating events to come(C) Remembering past experiences(D) Communicating emotions3. What is the purpose of the honeybee dance?(A) To determine the quantity of food at a site(B) To communicate the location of food(C) To increase the speed of travel to food sources(D) To identify the type of nectar that is available4. The word yet in line 15 is closest in meaning to(A) however(B) since(C) generally(D) so far5. What did researchers discover in the study of honeybees discussed in paragraph 2?(A) Bees are able to travel at greater speeds than scientists thought.(B) The bees could travel 25% farther than scientists expected.(C) The bees were able to determine in advance where scientists would place their food.(D) Changing the location of food caused bees to decrease their dance activity.6. It can be inferred from the passage that brain size is assumed to(A) be an indicator of cognitive ability(B) vary among individuals within a species(C) be related to food consumption(D) correspond to levels of activity7. Why are otters and mussel shells included in the discussion in paragraph 3?(A) To provide an example of tool use among animals(B) To prove that certain species demonstrate greater ability in tool use than other species(C) To illustrate how otters are using objects as tools(D) To demonstrate why mother chimpanzees show their young how to use tools8. The word rudimentary in line 20 is closest in meaning to(A) superior(B) original(C) basic(D) technical9. It can be inferred from the statement about mother chimpanzees and their young (lines 20-22)that young chimpanzees have difficulty(A) communicating with their mothers(B) adding quantities(C) making choices(D) opening hard nuts10. The phrase the one in line 24-25 refers to the(A) study(B) pair(C) chimpanzee(D) ability11. Scientists concluded from the experiment with chimpanzees and chocolate chips thatchimpanzees(A) lack abilities that other primates have(B) prefer to work in pairs or groups(C) exhibit behavior that indicates certain mathematical abilities(D) have difficulty selecting when given choicesPASSAGE 79 BDBDC AACDB C。
tpo45三篇托福阅读TOEFL原文译文题目答案译文背景知识
tpo45三篇托福阅读TOEFL原文译文题目答案译文背景知识阅读-1 (2)原文 (2)译文 (5)题目 (7)答案 (15)背景知识 (16)阅读-2 (16)原文 (16)译文 (19)题目 (23)答案 (30)背景知识 (31)阅读-3 (32)原文 (32)译文 (35)题目 (37)答案 (45)背景知识 (45)阅读-1原文The Beringia Landscape①During the peak of the last ice age,northeast Asia(Siberia)and Alaska were connected by a broad land mass called the Bering Land Bridge.This land bridge existed because so much of Earth’s water was frozen in the great ice sheets that sea levels were over100meters lower than they are today.Between25,000and10,000years ago,Siberia,the Bering Land Bridge,and Alaska shared many environmental characteristics.These included a common mammalian fauna of large mammals,a common flora composed of broad grasslands as well as wind-swept dunes and tundra,and a common climate with cold,dry winters and somewhat warmer summers.The recognition that many aspects of the modern flora and fauna were present on both sides of the Bering Sea as remnants of the ice-age landscape led to this region being named Beringia.②It is through Beringia that small groups of large mammal hunters, slowly expanding their hunting territories,eventually colonized North and South America.On this archaeologists generally agree,but that is where the agreement stops.One broad area of disagreement inexplaining the peopling of the Americas is the domain of paleoecologists,but it is critical to understanding human history:what was Beringia like?③The Beringian landscape was very different from what it is today. Broad,windswept valleys;glaciated mountains;sparse vegetation;and less moisture created a rather forbidding land mass.This land mass supported herds of now-extinct species of mammoth,bison,and horse and somewhat modern versions of caribou,musk ox,elk,and saiga antelope.These grazers supported in turn a number of impressive carnivores,including the giant short-faced bear,the saber-tooth cat,and a large species of lion.④The presence of mammal species that require grassland vegetation has led Arctic biologist Dale Guthrie to argue that while cold and dry, there must have been broad areas of dense vegetation to support herds of mammoth,horse,and bison.Further,nearly all of the ice-age fauna had teeth that indicate an adaptation to grasses and sedges;they could not have been supported by a modern flora of mosses and lichens. Guthrie has also demonstrated that the landscape must have been subject to intense and continuous winds,especially in winter.He makes this argument based on the anatomy of horse and bison,which do not have the ability to search for food through deep snow cover.They needlandscapes with strong winds that remove the winter snows,exposing the dry grasses beneath.Guthrie applied the term“mammoth steppe"to characterize this landscape.⑤In contrast,Paul Colinvaux has offered a counterargument based on the analysis of pollen in lake sediments dating to the last ice age.He found that the amount of pollen recovered in these sediments is so low that the Beringian landscape during the peak of the last glaciation was more likely to have been what he termed a"polar desert,"with little or only sparse vegetation,in no way was it possible that this region could have supported large herds of mammals and thus,human hunters. Guthrie has argued against this view by pointing out that radiocarbon analysis of mammoth,horse,and bison bones from Beringian deposits revealed that the bones date to the period of most intense glaciation.⑥The argument seemed to be at a standstill until a number of recent studies resulted in a spectacular suite of new finds.The first was the discovery of a1,000-square-kilometer preserved patch of Beringian vegetation dating to just over17,000years ago—the peak of the last ice age.The plants were preserved under a thick ash fall from a volcanic eruption.Investigations of the plants found grasses,sedges,mosses,and many other varieties in a nearly continuous cover,as was predicted by Guthrie.But this vegetation had a thin root mat with no soil formation,demonstrating that there was little long-term stability in plant cover,a finding supporting some of the arguments of Colinvaux.A mixture of continuous but thin vegetation supporting herds of large mammals is one that seems plausible and realistic with the available data.译文洞察白令地貌①在上一次冰期的高峰，东北亚地区（西伯利亚）和阿拉斯加曾由一片广阔的陆地相连，这片土地被叫做白令陆桥。
托福TPO3阅读真题原文题目及答案Part2
托福TPO3阅读真题原文题目及答案Part2托福TPO作为托福的模考工具，它的题目对于我们备考托福很有参考价值，为了帮助大家备考，下面小编给大家整理了托福TPO3阅读真题及答案Part2，望喜欢！托福TPO3阅读真题原文Part2Depletion of the Ogallala AquiferThe 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 wellsnow 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 of the 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 byusing 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.Paragraph 1: 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.托福TPO3阅读真题题目Part21.According to paragraph 1, which of the following statements about the High Plains is true?○Until farmers and rancher s settled there in the 1880s, the High Plains had never been inhabited.○The climate of the High Plains is characterized by higher-than-average temperatures.○The large aquifer that lies underneath the High Plains was discovered by the Ogallala Sioux Indians.○Before the early 1900s there was only a small amount of farming and ranching in the High Plains.Paragraph 2: 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.2. According to paragraph 2, all of the following statements about the Ogallala aquifer are true EXCEPT:○The aquifer stretches from South Dakota to Texas.○The aquifer's water comes from underground springs.○Water has been gatheri ng in the aquifer for 30,000 years.○The aquifer's water is stored in a layer of sandstone.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.○Despite the current impressive size of the Ogallala aquifer, the region's climate keeps the rates of water addition very small.○Although the aquifer has been adding water at the rate of only half a centimeter a year, it will eventually accumulate enough water of fill Lake Huron.○Because of the region's present climatic conditions, water is being added each year to the aquifer.○Even when the region experiences unfortunate climatic conditions, the rates of addition of water continue to increase.Paragraph 3: 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.4. The word "ensuing" in the passage is closest in meaning to○continuing○surprising○initial○subsequent5. In paragraph 3, why does the author provide the information that 40 percent of American cattle are fattened in the High Plains?○To suggest that crop cultivation is not the most importantpart of the economy of the High Plains○To indicate that not all economic activity in the High Plains is dependent on irrigation○To provide another example of how water from the Ogallala has transformed the economy of the High Plains○To contrast cattle-fattening practices in the High Plains with those used in other region of the United StatesParagraph 4: 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 of the irrigated acreage in Texas that is supported in 1980.6. The word "unprecedented" in the passage is closest in meaning to○difficult to control○without any restriction○unlike anything in the past○rapidly expanding7. The word "virtually" in the passage is closest in meaningto○clearly○perhaps○frequently○almost8. According to paragraph 4, all of following are consequences of the heavy use of the Ogallala aquifer for irrigation EXCEPT:○The recharge rate of the aquifer is decreasing.○Water tables in the region are becoming increasingly lower.○Wells now have to be dug to much greater depths than before.○Increasingly powerful pumps are needed to draw water from the aquifer.9. According to paragraph 4, compared with all other states that use Ogallala water for irrigation, Texas○has the greatest amount of farmland being irrigated with Ogallala water○contains the largest amount of Ogallala water underneath the soil○is expected to face the worst water supply crisis as the Ogallala runs dry○uses the least amount of Ogallala water for its irrigation needsParagraph 5: 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.10. The word "inevitable" in the passage is closest in meaning to○unfortunate○predictable○u navoidable○final11. Paragraph 5 mentions which of the following as a source of difficulty for some farmers who try to conserve water?○Crops that do not need much water are difficult to grow in the High Plains.○Farmers who grow crops that need a lot of water make higher profits.○Irrigating less frequently often leads to crop failure.○Few farmers are convinced that the aquifer will eventually run dry.Paragraph 6: 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 injectingcompressed 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.12.According to paragraph 6, what is the main disadvantage of the proposed plans to transport river water to the High Plains?○The rivers cannot supply sufficient water for the farmer's needs.○Increased irrigation costs would make the products too expensive.○The costs of using capillar y water for irrigation will increase.○Farmers will be forced to switch to genetically engineered crops.Paragraph 5: 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 ince ntive 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. █Paragraph 6: In the face of the upcoming water supply crisis, a number of grandiose schemes have been developed totransport 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.13.Look at the four squares [█] that indicate where the following sentence could be added to the passageBut even if uncooperative farmers were to join in the conservation efforts, this would only delay the depletion of the aquifer.Where would the sentence best fit? Click on a square to add the sentence to the passage.14.Directions: An introductory sentence for a brief summary of the passage is provided below. Complete 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 worth 2 points.The Ogallala aquifer is a large underground source of water in the High Plains region of the United States.●●●Answer choices○The use of the Ogallala for irrigation has allowed the High Plains to become one of the most productive agricultural regions in the United States.○Given the aquifer's low recharge rate, its use for irrigation is causing water tables to drop and will eventually lead to its depletion.○Releasing capillary water and introducing drought-resistant crops are less-promising solutions to the water supply crisis than bringing in river water○The periodic deepening of wells and the use of more-powerful pumps would help increase the natural recharge rate of the Ogallala.○In Texas, a great deal of attention is being paid to genetic engineering because it is there that the most critical situation exists.○Several solutions to the upcoming water supply crisis have been proposed, but none of them promises to keep the costs of irrigation low.托福TPO3阅读真题答案Part2参考答案：1. ○42. ○23. ○14. ○45. ○36. ○37. ○48. ○19. ○310. ○311. ○212. ○213. ○314. The use of the Ogallala for…Given the aquifer's low recharge…Several solutions to the upcoming…托福TPO3阅读翻译Part2奥加拉拉蓄水层的枯竭19世纪80年代，在美国中部北美大平原的广阔草原上定居着农场主们和牧场主们。
新托福TPO3阅读原文(三)The Long-Term Stability of Ecosystems及译文
新托福TPO3阅读原文(三):The Long-Term Stability of Ecosystems TPO-3-3：The Long-Term Stability of EcosystemsPlant communities assemble themselves flexibly, and their particular structure depends on the specific history of the area. Ecologists use the term “succession”to refer to the changes that happen in plant communities and ecosystems over time. The first community in a succession is called a pioneer community, while the long-lived community at the end of succession is called a climax community. Pioneer and successional plant communities are said to change over periods from 1 to 500 years. These changes—in plant numbers and the mix of species—are cumulative. Climax communities themselves change but over periods of time greater than about 500 years.An ecologist who studies a pond today may well find it relatively unchanged in a year’s time. Individual fish may be replaced, but the number of fish will tend to be the same from one year to the next. We can say that the properties of an ecosystem are more stable than the individual organisms that compose the ecosystem.At one time, ecologists believed that species diversity made ecosystems stable. They believed that the greater the diversity the more stable the ecosystem. Support for this idea came from the observation that long-lasting climax communities usually have more complex food webs and more species diversity than pioneer communities. Ecologists concluded that the apparent stability of climax ecosystems depended on their complexity. To take an extreme example, farmlands dominated by a single crop are so unstable that one year of bad weather or the invasion of a single pest can destroy the entire crop. In contrast, a complex climax community, such as a temperate forest, will tolerate considerable damage from weather to pests.The question of ecosystem stability is complicated, however. The first problem is that ecologists do not all agree what “stability”means. Stability can be defined as simply lack of change. In that case, the climax community would be considered the most stable, since, by definition, it changes the least over time. Alternatively, stability can be defined as the speed with which an ecosystem returns to a particular form following a major disturbance, such as a fire. This kind of stability is also called resilience. In that case, climax communities would be the most fragile and the least stable, since they can require hundreds of years to return to the climax state.Even the kind of stability defined as simple lack of change is not always associated with maximum diversity. At least in temperate zones, maximum diversity is often found in mid-successional stages, not in the climax community. Once a redwood forest matures, for example, the kinds of species and the number of individuals growing on the forest floor are reduced. In general, diversity,by itself, does not ensure stability. Mathematical models of ecosystems likewise suggest that diversity does not guarantee ecosystem stability—just the opposite, in fact. A more complicated system is, in general, more likely than a simple system to break down. A fifteen-speed racing bicycle is more likely to break down than a child’s tricycle.Ecologists are especially interested to know what factors contribute to the resilience of communities because climax communities all over the world are being severely damaged or destroyed by human activities. The destruction caused by the volcanic explosion of Mount St. Helens, in the northwestern United States, for example, pales in comparison to the destruction caused by humans. We need to know what aspects of a community are most important to the community’s resistance to destruction, as well as its recovery.Many ecologists now think that the relative long-term stability of climax communities comes n ot from diversity but from the “patchiness”of the environment, an environment that varies from place to place supports more kinds of organisms than an environment that is uniform. A local population that goes extinct is quickly replaced by immigrants from an adjacent community. Even if the new population is of a different species, it can approximately fill the niche vacated by the extinct population and keep the food web intact.译文：TPO-3-3 生态系统的长期稳定植物群体可以自由地聚集，它们特殊的结构取决于聚集区域的具体历史。
老托福阅读100篇passage33试题及答案
老托福阅读100篇passage33试题及答案为了帮助大家备考托福阅读，提高成绩，下面小编给大家带来老托福阅读100篇passage 33试题及答案，希望大家喜欢!老托福阅读100篇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 andremember. 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 atonce (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) predictPASSAGE 33 ADADC ABDBB C托福阅读怎么抓住定位词首先介绍一下，什么是定位词?其实很简单，打个比方，你和朋友约好了去酒吧，朋友和你说酒吧在沈阳新东方正对面，这个酒吧你是不知道地点的，也就是你的目的地;而新东方却很熟知，那么你只需找到新东方便可以找到酒吧了。
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Paragraph 1: Since 1980, the use of wind to produce electricity has been growing rapidly. █In 1994 there were nearly 20,000 wind turbines worldwide, most grouped in clusters called wind farms that collectively produced 3,000 megawatts of electricity. █Most were in Denmark (which got 3 percent of its electricity from wind turbines) and California (where 17,000 machines produced 1 percent of the state’s electricity, enough to meet the residential needs of a city as large as San Francisco). █In principle, all the power needs of the United States could be provided by exploiting the wind potential of just three states—North Dakota, South Dakota, and Texas. █
一定是有粘连的 步骤：通读原句，敲定关系，构造内容，寻求对应
Paragraph 1: Since 1980, the use of wind to produce electricity has been growing rapidly. █In 1994 there were nearly 20,000 wind turbines worldwide, most grouped in clusters called wind farms that collectively produced 3,000 megawatts of electricity. █Most were in Denmark (which got 3 percent of its electricity from wind turbines) and California (where 17,000 machines produced 1 percent of the state’s electricity, enough to meet the residential needs of a city as large as San Francisco). █In principle, all the power needs of the United States could be provided by exploiting the wind potential of just three states—North Dakota, South Dakota, and Texas. █
Look at the four squares [■] that indicate where the following sentence could be added to the passage. Some companies in the power industry are aware of this wider possibility and are planning sizable wind-farm projects in states other than (译为而不 只是，本句前一定有California)California. Where would the sentence best fit?
----Insertion questions -----Sentence Simplification questions
Paragraph 1: Since 1980, the use of wind to produce electricity has been growing rapidly. █In 1994 there were nearly 20,000 wind turbines worldwide, most grouped in clusters called wind farms that collectively produced 3,000 megawatts of electricity. █Most were in Denmark (which got 3 percent of its electricity from wind turbines) and California (where 17,000 machines produced 1 percent of the state’s electricity, enough to meet the residential needs of a city as large as San Francisco). █In principle, all the power needs of the United States could be provided by exploiting the wind potential of just three states—North Dakota, South Dakota, and Texas. █
Tips:
任何情况下，做插入题应该先句子(待插入句子)，后读段落 正常来说，段落本身是完整的，不缺句子，待插入的句子本身可有可无，不是中 心句
不能使用语感做题，一定要去黑体字中寻找具体的粘连（this, other than） 松紧程度不一致，先使用紧凑粘连(this),后使用松散粘连（other than） 紧凑粘连：代词性粘连，代词不能隔句子指代 松散粘连：非代词性粘连，只要求前文出现，不要求紧跟