历年托福考试阅读真题汇总含答案

1、0308托福试题阅读(55minutes )Question 1-11If food is allowed to stand for some time, itputrefies . When the putrefied materialis examined microscopically ,it is found to be teeming with bacteria. Where do thesebacteria come from , since they are not seen in fresh food? Even until the mid-nineteenthcentury,

2、 many people believed that such microorganisms originated by spontaneous(5 ) generation ,a hypothetical process by which living organisms develop from nonlivingmatter.The most powerful opponent of the theory of spontaneous generation was the French chemistand microbiologistLouisPasteur(1822-1895) .P

3、asteur showed that structurespresentin air closely resemblethemicroorganisms seen in putrefying materials .He did(10) this by passing air through guncotton filters, the fibers of which stop solid particles. Afterthe guncotton was dissolved in a mixture of alcohol and ether, the particles that it had

4、trapped fell to the bottom of the liquid and were examined on a microscope slide . Pasteurfound that in ordinary air these exists a variety ofsolid structures ranging in size from0.01 mmto more than1.0 mm .Many of thesebodies resembled the reproductive(15)structuresof common molds, single-celledanim

5、als, and various other microbial cells .As many as 20 to 30 of them were found in fifteenliters of ordinary air ,and they couldnot be distinguished from the organisms found in muchlargernumbersinputrefy ingmaterials . Pasteurconcluded that the orga ni smsfound in putrefying materials originatedfrom

6、the organized bodies present in the air .Hepostulated that these bodies are constantly(20)being deposited on all objects.Pasteur showed that if a nutrient solution wassealed in a glass flask and heated toboiling to destroy all the living orga ni sms contaminatingit, it never putrefied. Thethe air in

7、 sideproponents of spontaneous generation declared that fresh air was necessary forspontaneous generation and that the sealed flask was affected in some way(25)by heating spontaneousso that it wouldno longer supportgeneration.Pasteur constructedswan-neckedflask in which putrefying materialscould he

8、heated to boiling, but aircould reenter. The bends in the neck preve nted microorganismsfrom getting in the flask.Material sterilized in such a flask did not putrefy.1, What does the passage mainly discuss?(a) Pasteur ' sinfluence on the development of the microscope.(b) The origin of the theory

9、 of spontaneous generation .(c) The effects of pasteurization on food.(d) Pasteur ' s argument agai nst the theory of spontaneous generation .2, The phraseteeming with”n line 2 is closest inmeaning to(a) full of(b) developing into(c) resistant to(d) hurt by3, Which of the following questions did

10、 the theory of spontaneous generation attempt to answer? (a)What is the origin of the living organisms are seen on some food?(b) How many types of organisms can be found on food?(c) What is the most effective way to prepare living organisms for microscopic examination? (d)How long can food stand bef

11、ore it putrefies?4, The word resemble ”n line 9 is closest in meaning to(a) benefit from(b) appear similar to(c) join together with(d) grow from5, Thepurpose of the guncotton ” mentioned inparagraph 2 was to(a) trap particles for analysis(b) slow the process of putrefaction(c) increase the airflow t

12、o the microscopic slide(d) aid the mixing of alcohol and ether6, The author mention1.0mm ” in line 14 in describing the(a) thicknessof a layer of organisms that wasdeposited on an object(b) diameterof the fibers that were in the guncottonfilters(c) thickness of the microscope slides that wereused (d

13、)size of the particles that that were collected meaning to7. Theword postulatedinline19 is closest in(a) analyzed(b) doubted(c) persuaded(d) suggested8. The objects that Pasteut removed from the air in his experiment were remarkable because they were(a) primarily single-celled organisms(b) nodiffere

14、nt from objects found in putrefy ingmaterials(c) fairly rare(d) able to live in a mixture of alcohol and ether9. The word“t ” in line 22 refers to (a)anutrient solution(b) a glass flask(c) boiling(d) spontaneous generation10. Accordingto paragraph 3,proponents of spontaneousgeneration believed that

15、which of the following was important forthe process to succeed ?(a) A sealed container(b) Fresh air(c) Heat(d) The presence of nutrients11t can be inferred from paragraph 3 that Pasteuremployed a swam-necked flask to(a) store sterilized liquids for use in future experiments(b) preve nt heat from bui

16、ldi ng up in a soluti on(c) disprove a criticism of his con clusi ons(d) estimate the number of organisms in a liter of airQuestions 12-20In the early decades of the United States ,the agrarian movement promoted the farmeras society'her o.In the minds of agraria nthinkers and writers ,the farmer

17、 was a person on whosewell-beingthe health of the new countrydepended . The period between theRevolution, which ended in 仃 83,andthe CivilWar ,which ended in 1865 ,was the age of(5 )the farmer in the United States . Agrarian philosophers ,represented most eloquently byThomasJefferson,celebratedfarme

18、rsextravagantly for their supposed centrality in a goodsociety, their political virtue ,and their Superior morality . And virtually all policy makers, whether they subscribed to the tenets of the philosophy held by Jefferson or not, recognized agriculture as the key componentof theAmerica neconomy .

19、 Consequently ,government at(10) all levels worked to encourage farmers as a social group and agriculture as economicenterprise.Both the national and state governments developed transportation infrastructure,building canals, roads, bridges, and railroads ,deepening harbors ,and removing obstructions

20、fromnavigable streams . The national government imported plant and animal varieties and(15) launched exploring expeditions intoprospectivefarmlands in the Westn addition ,government trade policies facilitated the exportingof agricultural products.For their part farmers seemed to meet the social expe

21、ctations agrarian philosophershad for them ,as their broader horizons and greater self-respect,both products of theRevolution ,were reflected to some degree in their behavior . Farmers seemed to become(20) more scientific ,joining agricultural societiesand reading the farm newspapers that sprangup t

22、hroughout the country . They began using improved implements, tried new crops andpure animal breeds , and became more receptive to modern theories of soil improvement .They also responded to inducements by nationaland state governments . Farmersstreamed to the West ,filling frontier lands with stunn

23、ing rapidity . But farmers responded(25) less to the expectations of agrarians and government inducements than to growing market opportunities . European demand for food from theUnited States seemed insatiableWar,industrialization, and urbanization all keptdemand high in Europe . United States citie

24、sand industries grew as well; even industries not directly related to farming thrived becauseof the market, money ,and labor that agricultureprovided .12. What does the passage mainly discuss?(a) The agrarian philosophy of Thomas Jefferson(b) Therole of the national government in thedevelopment of a

25、griculture(c) lmprovements in farming techniques(d) The impact of the increased importance of the farmer13. Theword depended ” in line 3 is closest inmeaning to(a) improved(b) relied(c) demanded(d) explained14. Theauthor mentions Thomas Jefferson inparagraph 1 as an example of(a) a leader during the

26、 Revolution(b) an inventor of new farming techniques(c) a philosopher who believed farmers wereessential to the creation of a good society(d) a farmer who guided the agrarian movement toward ansubscribed to ” inline 8 is closestemphasis on economic development15. The phrase in meaning to(a) contribu

27、ted to(b) agreed with(c) thought about(d) expanded on16. Which of the following statements is supported bythe information in paragraph 1?(a) AIIgovernmentpolicy makers acceptedJefferson ' s views of agriculture and farmers.(b) Agriculturalproduction declined between 1783and 1861.(c) Themajority

28、of farmers worked for thegovernment.(d) Agriculturewas a vital part of the nation "secono my.17. According to the passage , the national and stategovernments did all of the following EXCEPT(a) build roads(b) import new plant varieties(c) give farmers money for their crops(d) develop policies th

29、at helped farmers export their products18. All of the following are mentioned as examples offarmers ' meeting the expectations of agra rian philosophers EXCEPT(a) obtaining information from farm newspapers(b) accumulating personal wealth (c)planting new crops(d) becoming more scientificin line 2

30、4 is closest in19. Theword stunningmeaning to(a) predictable(b) impressive(c) famous(d) gradualstatements is best20. Which of the followingsupported by paragraph 4?(a)Agriculturaldevelopmentcontributedtodevelopment in other parts of the economy.(b)European agriculturalproducts were of a higherqualit

31、y than those produced in the United States.(c)The growingsettlement of the West led to adecrease in agricultural productio n.(d) Farmers were influenced more by government policies than by market opportunities.Question 21-29The wide variety of climates in North Americahas helped spawn a complex patt

32、ern ofAmerica.”soil regions. In general, the realm ' soils also reflect the broad environmental partitioninginto humid America ” and aridWhere annual precipitation exceeds 20 inches(50 centimeters),soilsin humid areasacidic in chemical content, Since crops(5 ) do best in soils that are neither a

33、cidic(higher in acid content) nor alkaline(higher content). fertilizationis necessary todesired level of neutrality between the two. Arid America ' soils are typically alkalinetendinachieveto besalttheand must be fertilized back towardneutralityby adding acidiccompo unds.Although many of these d

34、ryland soils, particularlyin the Great Plains, are quite fertile, European settlers learned over a century ago that(10) water is the main missing ingredient in achieving their agricultural potential .In the1970 ',certain irrigationmethods wereperfected and finally provided a real opportunityto e

35、xpand more intensive farming west fromthe Central Lowland into the drier portionsof the Great Plains. Glaciation also enhanced therich legacy of fertile soils in the centralUnited States,both from the deposition of mineral-rich glacial debris left by meltwater(15) and from thick layers of fine wind-

36、blown glacial material, called loess, in and around themiddle Mississippi Valley.Natural vegetationpatternsdisplayed on a map of North America, but the enormous human modificationcouldbeofthe NorthAmerican environment in modern times hasschemetodichotomyisall but reduced this regionalization the lev

37、el of the hypothetical. Nonetheless,(20) the humidAmerica-aridAmericastill a valid generalization: the naturalvegetation of areas receiving more than 20 inches of water yearly is forest, whereas thedrier climates give rise to a grassland cover. The forests of North America tent to makea broad transi

38、tion by latitude.In the CanadianNorth, needle-I eaf forests dominate, butthese coniferous trees become mixed with broadleaf deciduous trees as one crosses the(25) border into the Northeast United States. As oneproceeds toward the Southeast,broadleafvegetation becomes dominant. Arid America mostly co

39、nsists of short-grass prairies or stepper.The only areas of true desert are in theSouthwest.21 What aspect of North America does the passage mainly discuss?(A) The wide variety of climates(B) Soil types and vegetation patterns(C) Improved irrigation methods and the expansionof agriculture(D) The cha

40、nge in precipitation patterns22 The word spawn ”n line 1 is closest in meaning to(A) d istinguish(B) eliminate(C) protect(D) create23 The word partitioning”n line 2 is closest inmeaning to(A) d ivisio n(B) modification(C) opening(D) circulating24 According to the passage, acidic soils tent to be ass

41、ociatedwith(A) a high salt content(B) an increase in farming(C) large amounts of rain(D) glacial meltwater25 The word enhanced ”n line 13 is closest in meaning to(A) implied(B) increased(C) in dicated(D) informed26 How did glacial meltdown affect the soil inNorth America?(A) It redistributed the soi

42、l types(B) It added salt to the soil(C) It made the soil more neutral in content(D) It added minerals to the soil27 The phraseth i sregionalization scheme ” inline 19 refers to the(A) m ovements of glacial deposits(B) patterns of natural vegetation(C) humanmodificationofthe NorthAmerica nenvironment

43、(D)disti notionAmericabetweenhumidAmericaand arid28 The wordmeaning totransition” inline 23 isclosestin(B)change(C)advantage(D)condition29The passagesupportswhichof thefollowi ngstatements?(A) Arid Americais not necessarilycharacterizedby(A) elevationthe presence of desertsUn ited(B) Most of Canada

44、and the northeasternStates consists of short-grass prairies wherever natural(C) The accumulationof loess isprimarilythevegetation has not been modified by humansresult of irrigation(D) Glaciation removed the fertile layer of soilfrom much of the Mississippi ValleyQuestions 30-40Most sources of illum

45、inationgeneratelightover an appreciable period, and indeed ifan object is lit for a very brieftime(lessthat1/25 second), the human eye will not react in time to see the object. Ais, a light -sensitiveemulsion-thatphotographic coating onphotographic film, paper, or glass-will, however, record much sh

46、orter bursts of light. A(5 ) photographic flash can therefore capture high-speed movement on film as wellbe used toas to correctdeficienciesof theno rmalsurrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containingmagnesiumwir

47、e and some oxygen-richsubstance, such as potassium chlorate. When thebag was ignited, the metal burned with an intense flash. A contemporary observer reported(10) that“hisquiteunsafe device seemsto havedone nothing worse that engulf the room indensesmoke and leadto pictures ofdubiousquality and odd

48、pose s. ”The evolution of the photoflash was slow, flashbulbs, containing fine wire made of ametal, such as magnesium or alu minum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920' s. In the e arliest type, the metal(15) was separated fr

49、om the oxygen by a thin glass bulb. Theflash was fired by piercing thebulb and allowing the oxygen to come into contactwith the metal, which ignitedspontaneousl y. Later bulbs were fired by an electric battery, which heated the wire bypassing a small current through it. Other combinations, suchas th

50、e pairing of oxygen difluoride with zirconium, have also been used.In each case enough energy is given out to(20) heat the oxidizable metal momentarily to awhite-hotemission of visible light. The smokeparticles are so small that they cool rapidly; but since they are white, they contribute to the bri

51、lliance by reflecting the light from their still - glowing neighbors. A slightly bigger form of the metal will burn for a longer time.30 What does the passage mainly discuss?(A) The history of the photoflash(B) Theories about how the eye reacts to light(C) The technology of modern photography(D) The

52、 dangers of using the early photoflash31 According to the passage,1/25 second is the minimum amount of time required for the(A) r ecording of an image on film(B) generation of artificial light(C) creation of a photographic emulsion(D) human eye to react to light32 According to the passage, an advant

53、age of using a photoflash is that it(A) can produce repeated bursts of light(B) intensities colors in photographs(C) is short enough not to bother human eyes(D) supplements existing lighting(A) set on fire(B)cut into(C)opened(D)shaken34 Which of the following phrases is defined in paragraph 1?(A) ”

54、appreciable period”(li ne 1)(B) ” photographic emulsion” (li ne 3)(C) ” high- speed movement” (line 5)(D) ” odd poses”(line 11)35 The wo rdevolution”nline12 is closest inmeaning to(A) p ublicity(B)adoption(C)development(D)manufacture36 The function of the glass in the first flashbulbs was to(A) p ro

55、duce the spark that initiated the flash(B) magnify the light produced by the flash(C) protect the photographer from the heat of the flash(D) keep the metal and oxygen apart before theflash(A) oxygen(B) battery(C) wire(D) current38 The wordmomentarily ” in line 20 is closest inmeaning to(A) effortles

56、sly(B) briefly(C) electronically(D) gradually39 According to the passage, the white color of the smokeparticles generated by a flashbulb contributes to(A) r apid cooling(B) bright illumination(C) electrical conductivitybe(D) intense heat40 According to the passage, a flashbulb can made to burn longer by using(A) thicker wire(B) more oxygen(C) thinner glass(D) continuous electricityQuestions 41-50The stylistic innovation in paining