2022-2023年湖南省怀化市大学英语6级大学英语六级知识点汇总（含答案）

2022-2023年湖南省怀化市大学英语6级大学英语六级知识点汇总（含答案）学校:________班级:________姓名:________考号:________

一、2.ReadingComprehension(SkimmingandScanning)(20题)1.Duringthe20thcentury,______,abundantconflictsinusedemand,andanintensificationofusethathasacceleratedquickly.

2.

ThethreearrestedinSudanwereregardedas______bylocalauthorities.

3.

Mr.Bailey,the"monkeyartist",preferstofinishitsdrawingwiththehelpofothers.

A.YB.NC.NG

4.

TheexamplethatSourwoodchangescolorsbeforeotherspeciesdoillustratethatthetimingofcolorchange______.

5.

AU.S.scientificreportconcludedthatsometrendsofclimatechangewerecausedby______.

6.

AccordingtoscientistsattheU.S.NationalSnowandIceDataCenter.withinabout60years,therewillbe______ontheArcticOcean.

7.

Sophisticated______techniqueshavebeenalreadyemployedtocalculatehowintermarriageischangingthefaceoftheUnitedStates.

8.

Wecannotsolvethepollutionproblem.

A.YB.NC.NG

9.

WeshouldpromoteandprotecttheInternetasaprimarynetworkinorderto______.

10.

Inordertohealthepainofanabusedperson,weshould______.

A.improveoureducation

B.punishthebadguys

C.showhimourcompassion

D.maketheworldabetterplace

11.Wal-Mart

Wal-Martismorethanjusttheworld'slargestretailer.Itisaneconomicforce,aculturalphenomenonandalightningrodforcontroversy.ItallstartedwithasimplephilosophyfromfounderSamWalton:Offershopperslowerpricesthantheygetanywhereelse.ThatbasicstrategyhasshapedWal-Mart'scultureanddriventhecompany'sgrowth.

NowthatWal-Martissohuge,ithasunprecedentedpowertoshapelabormarketsgloballyandchangethewayentireindustriesoperate.

HistoryofWal-Mart

SamWaltonopenedhisfirstfive-and-dimein1950.Hisvisionwastokeeppricesaslowaspossible.Evenifhismarginsweren'tasfatascompetitors,hefiguredhecouldmakeupforthatinvolume.Hewasright.

Intheearly1960s,WaltonopenedhisfirstWal-MartinRogers,Arkansas.Thecompanycontinuedtogrow,goingpublicin1970andaddingmorestoreseveryyear.In1990,Wal-MartsurpassedkeyrivalKmartinsize.Twoyearslater,itsurpassedSears.

Waltoncontinuedtodriveanoldpickuptruckandsharebudget-hotelroomswithcolleaguesonbusinesstrips,evenafterWal-Martmadehimveryrich.Hedemandedthathisemployeesalsokeepexpensestoabareminimum—amentalitythatisstillaltheheartofWal-MartculturemorethanadecadeafterWalton'sdeath.Thecompanyhascontinuedtogrowrapidlyafterhisdeathin1992andnowoperatesfourretaildivisions—Wal-MartSupercenters,Wal-Martdiscountstores,NeighborhoodMarketstoresandSam'sClubwarehouses.

Wal-MartStrategy

Let'sstartwithtechnology.Wal-Martpushedtheretailindustrytoestablishtheuniversalbarcode,whichforcedmanufacturerstoadoptcommonlabeling.Thebarallowedretailerstogenerateallkindsofinformation—creatingasubtleshiftofpowerfrommanufacturerstoretailers.Wal-Martbecameespeciallygoodatexploitingtheinformationbehindthebarcode.Andthusitisconsideredapioneerindevelopingsophisticatedtechnologytotrackitsstockandcutthefatoutofitssupplychain.

Recently,Wal-Martbecamethefirstmajorretailertodemandmanufacturersuseradiofrequencyidentificationtechnology(RFID).Thetechnology,usesradiofrequenciestotransmitdatastoredonsmalltagsattachedtopallets(货盘)orindividualproducts.RFIDtagsholdsignificantlymoredatathanbarcodes.

Thefrugalculture,establishedbyWalton.alsoplaysintoWal-Mart'ssuccess.Thecompanyhasbeencriticizedfortherelativelypoorwagesandhealthcareplansthatitotterstorank-andfileemployees.Ithasalsobeenaccusedofdemandingthathourlyworkersputinovertimewithoutpay.Storemanagersoftenworkmorethan70hoursperweek.

Thiscultureisalsopresentatthecompany'sheadquarters.Wal-MartisheadquarteredinBentonville,Arkansas,insteadofanexpensivecitylikeNewYork.Thebuildingisunattractiveanddull.Youwon'tcatchexecutivesinqualitycarsandyouwon'tseethemdraggingintoworkat9:30a.m.Executivesflycoachandoftensharehotelroomswithcolleagues.Theyworklonghours,typicallyarrivingatworkbefore6:30a.m.andworkinghalfdaysonSaturdays.

ThecentralgoalofWal-Martistokeepretailpriceslow—andthecompanyhasbeenverysuccessfulatthis.ExpertsestimatethatWal-Martsavesshoppersatleast15percentonatypicalcartofgroceries.Everything—includingthetechnologyandcorporateculture—feedsintothatultimategoalofdeliveringthelowestpricespossible.Wal-Martalsopushesitssuppliers,somesaycruelly,tocutprices.InTheWal-MartEffect,authorCharlesFishmandiscusseshowthepriceofafour-packofGElightbulbsdecreasedfrom$2.19to88centsduringafive-yearperiod.

ThePower

BecauseofWal-Mart'smassivesize,ithasincrediblepower.Ithasdrivensmallerretaile

A.productsatlowerprice

B.anykindofgoodsthecustomersmaywant

C.amorecomfortableshoppingenvironment

D.free-of-chargepackaging

12.

Nexttocoal-burningpowerplants,______arethesecondlargestU.S.sourceofcarbondioxidepollution.

13.

ThisarticletellsusthatfurtherstudiesareneededtoassessthepotentialrisksofGMfoodseventhoughthetechnologypromisesmanybenefits.

A.YB.NC.NG

14.

Inthe1960SouthAmericatsunami,whenthethirdwavecame,itreachedtheheightof______.

15.

Antipollutionlegislationshavebeenenactedthankstothecontinuedpressurefrom______.

A.grass-rootsorganizations

B.individualactivism

C.environmentalists

D.environmentalregulation

16.

Despitethedeclineofthedeathtollinahurricane,thecostsofthedamageareincreasinggreatlyinthe20thcentury.

17.

Aspigeonsaretrainedtogetbackhome,theydonothavethepowerasothermigratorybirdshave.

A.YB.NC.NG

18.Withinternetseeninalmosteverycorneroftheworld,today'sworldissaidtohavebecome

19.

Iftheproblemisapsychologicalone,wecan'tattemptto______.

20.

PaulwasconcernednotonlyabouthisownsafetybutaboutthesafetyofhisSudanesedriverandinterpreter.

A.YB.NC.NG

二、3.ListeningComprehension(20题)21.(25)

A.Sixmonthsago.

B.Threemonthsago.

C.Oneyearago.

D.Twoyearsago.

22.(22)

A.Cancer.

B.Heartdisease.

C.Organtransplant.

D.Lungdisease.

23.(24)

A.Sheworksatthemeatcounter.

B.Sheputsgroceriesoutontheshelves.

C.Shecarriesgroceriesoutofthestoreforcustomers.

D.Shechecksthequalityofmilkproducts.

24.SectionB

Directions:Inthissection,youwillhear3shortpassages.Attheendofeachpassage,youwillhearsomequestions.Boththepassageandthequestionswillbespokenonlyonce.Afteryouhearaquestion,youmustchoosethebestanswerfromthefourchoicesmarkedA,B,CandD.

听力原文：Stressisaverynormalpartoflife.Mostpeoplefeelstressatsometimeintheirlives.

Itdoesn'tcomefromaneventitself,thatis,fromthethingsthatarehappeninginourlife.Itcomesfromthemeaningwegivetowhathashappened.Wecanexperiencestressanytimewefeelwedon'thavecontrol.Itisthebody'swayofshowinganxietyorworry.Stressisnotjustcausedbyourmentaloremotionalcondition,itisalsoinfluencedbyhowtiredwearewhetherwehaveabalanceddietwithenoughvitaminsandminerals,whetherwegetenoughphysicalexercise,andwhetherwecanrelax.

Ifwefeelstressed,thereareseveralthingsthatwecando.First,weneedtolearnhowtorelaxandbreatheslowly,andsmoothly.

Wecanalsotakesometimeoutofourworried,busyscheduletonoticethesmallthingsinlife.Smelltheair,lookattheflowers,noticethesmalldesignsintheleavesonatree—theseactivitiescandomuchtoquietusandtogiveourselvesasmallbreakinabusyschedule.

Weneedtotakecareofourbodies.Beingtiredmakesiteasierforustogetsickandtodevelopphysicalproblemsrelatedtostress.Weneedtogetenoughrest,eatwell,anddosomeregularexercise.

Finally,weneedtofindwhatiscausingthestressinourlives.Oncewehave'foundit,weneedtobegintochangethatpartofourlives.Ifwebelievethatwecancontrolstress,wecanbegintocontrolourlives.

(27)

A.Anunexpectedeventthathappens.

B.Yourunderstandingofanevent.

C.Thethingsthathappeninourlives.

D.Thementioningoftheworditself.

25.(34)

A.OniPodyoucanwatchallTVprogramsofABC

B.TwoABChitsareavailableoniPod.

C.TheiPodwilljoindigitalvideorecordersandDVDs.

D.TheiPodbegantoproduceitsownprograms.

26.(40)

27.

【B10】

28.(21)

A.Cinemas.B.Stageshows.C.Nightclubs.D.Discos.

29.(36)

A.Lossoflifeandproperty.

B.After-effects.

C.Brokentransportationsystem.

D.Weakeco-system.

30.听力原文：Atpresent,humanbeingshaveusedmanydevicestomeasuretime.Perhaps,thesundialwas,oneoftheearliestandsimplestdevices.Asundialcanmeasurethemovementofthesunacrosstheskyeachday.

Thesundialworkedverywellonlywhenthesunwasshining.Sootherwaysofmeasuringthepassingoftimewereinventedatthattime.Onedevicewasthehourglass.Itusedathinstreamoffallingsandtomeasuretime.

Bythe1700s,peoplehadalreadydevelopedmechanicalclocksandwatches.Andtodaymanyofourclocksandwatchesareelectronic.

Sowehavedevicestomarkthepassingoftime.Butwhattimeisitnow?Clocksindifferentpartsoftheworlddonotshowthesametimeatthesametime.Asinternationalcommunicationsandtravelgrew,itbecameclearweneedawaytoestablishacommontimeforallpartsoftheworld.

In1884,aninternationalconferencedividedtheworldinto24timeareasorzones.Eachzonerepresentsonehour.TheastronomicalobservationinGreenwich,England,waschosenasthestartingpointforthetimezone.

Mostpeoplehavenotroubleinagreeingthattimemovesforward.Somescientistsbelievethereisonereasonwhytimemovesforward.Itisclearweneedawaytoestablishacommontimeforallpartsoftheworldwithscientificlaw:thesecondlawofthermodynamics.Thelawsaysdisorderincreaseswithtime.

(33)

A.Itmeasuresthelengthofadayandanight.

B.itmeasuresthemovementofthesuneachday.

C.Itmeasuresthepassingofhours,minutesandperhapsseconds.

D.Itmeasurestheshadowofthestickacrosstheflatsurfaceofthesundial.

31.听力原文：Scientistshavediscoveredthatplantsthemselvesproducemanypoisonouschemicalsfordefenseagainstinsects.Butinsectshavedevelopedwaysofdealingwiththem.Guesshowmanyyearshavetheinsectsbeeneatingplants.Thenumberitselfwillscareyou.Infact,insectshavebeeneatingplantsforasmanyas250millionyears.Nowinsectsareusingthesesamemechanismstodealwithman-madepoisons—insecticides.Thisiswhyresistanceofinsectstoinsecticideshasdevelopedsorapidly.

Whatshouldbedone?Scientistsstudyingtheproblemsuggestthatfarmersuselessinsecticides.Atthemoment,farmersregularlyspraycropsasaprecautionagainstproblemsthatarecausedbylargenumbersofpests.Theyshould,instead,sprayonlywherepestshaveactuallybeenseen.Secondly,farmerscoulduseacombinationoftwoorthreeinsecticidesatonce.Tosurvive,theinsectswouldneedtobecomeresistanttotwoormoreinsecticidesatthesametime.

Themostsurprisingsuggestion,perhaps,isthatatcertaintimesoftheyear,farmersshouldactuallytrytoattractnewinsectsontothecropstheyaretryingtoprotect.Thenewinsectswillmatewiththosewhichsurvivedfromacertainkindofinsecticideandwilllessenthelatter'sresistancetoit.

Scientistshopethattheseandothermeasureswillpostponethedaywhenfarmersandscientistswillhavetostandbywhilenewsuper-bugswhichmayberesistanttoallpoisonsinvadeourfarmsanddevourourcrops.

(33)

A.Insectshavedevelopedsomesortofresistancetoman-madepoisons.

B.Insectshavebeeneatingplantsforabout250millionyears.

C.Farmerssometimesuseacombinationoftwoorthreeinsecticidesatonce.

D.Newinsectsmatewithinsecticide-survivinginsects.

32.(15)

A.Becausetheyhavesomefinancialproblems.

B.BecausetherewillbemuchraininMay.

C.Becausetheywon'thavefreetimeinMay

D.Becausetheycan'thaveeverythinggotreadybythen.

33.听力原文：Isyourfamilyinterestedinbuyingadog?Adogcanbeahappyadditiontoyourfamily,butifyouchoosethewrongkindofdog,theconsequencescancauseyoualotoftrouble.

Familiesshouldsitdownandthoroughlydiscusstheproblemsinvolvedbeforebuyingadog.[29]Evenifthechildreninyourfamilyaretheoneswhowantthedog,theparentsaretheoneswhoarereallyresponsibleforseeingthattheanimalisproperlycaredfor.Ifyoudon'tknowmuchaboutdogs,it'sagoodideatogotothelibraryortheASPCAforbooksaboutvariouskindsofdogs,aswellasbooksabouthowtotrainapuppy.Inreadingaboutthedifferentbreeds,youshouldknowthatadogdescribedasveryalertmaybetoojumpyandbouncy.Whenabookdescribesadogasanidealhuntingdog,itprobablymeansthatthedogwon'tbehappylivinginasmallapartment.Dogbreedsvaryinpopularityastheyearsgoby.[30]OneofthemostpopulardogsthesedaysistheGermanshepherd,thisisbecauseitprovidesprotectionaswellascomRanionship.Thefamilyshouldbewarnedthatthesedogsgrowuptobeverybig,andmaybetoopowerfulforchildrentohandle.Ifspaceislimited,atoydogmaybeagoodchoice.Theredogsareverysmallandeasytotrain.[3]Theydon'tneedtobewalkeddaily,sincetheycanexerciseinthespaceavailableinthehome.

(33)

A.Children.B.Family.C.Parents.D.ASPCA

34.

【B5】

35.SectionB

Directions:Inthissection,youwillhear3shortpassages.Attheendofeachpassage,youwillhearsomequestions.Boththepassageandthequestionswillbespokenonlyonce.Afteryouhearaquestion,youmustchoosethebestanswerfromthefourchoicesmarkedA,B,CandD.

听力原文：Ifyou'reinchargeofaproject,thekeytosuccessisgettingeveryonetohelpyou.Asadirector,Isuggest,IgentlypushtheactorsinthedirectionIwantthemtogo.

Inthe1986movieNothinginCommon,JackieGleason'scharacter.MaxBasner,getsfiredfromhisjobasaclothingsalesman.Thescene,shotonaboat,showsMax'shopelessnessaboutbeingoutofwork.IwaslookingforsomewaysthatwouldallowMaxtoshowhisfeelings.

JackiehadfarmoreexperienceateverythingthanIdid,andatfirstIwasfrightened.WhatcouldIpossiblytell"TheGreatOne"aboutacting?OutoffearIdecidedtodirectbysuggestion,andIsatdownwithGleasontotalkaboutthescene."SoMaxissad,right?"Isaid.Gleasonnodded.

"Andhe'sprobablystillcarryinghispenswithhisnameonthem--theonesheusedtohandouttohiscustomers,right?"Gleasonnodded.

"Sowhatwouldyouwanttodowiththepensafteryouwerefired?"

Hewassilentforamoment."Whydon'tIthrowthemoverboard?"

Istoodupandturnedtowardthecrew."Hey,everybody,Jackiehasawonderfulidea.Let'sshootit."

Afterfilmingthescene,Gleasoncalledmeoverandsaidwithasmile,"Garry,whatkindofwonderfulideaamIgoingtohavetomorrow?"

Youandyourteamcandiscovertheanswerstoproblemstogether.Whentherearenoprizesorgoldstarsforthosewhogetthesolutionfirst,you'llallbenefitwheneverythingturnsoutright.

(27)

A.Makeeveryoneworkforyou.

B.Geteveryonetohelpyou.

C.Letpeopleknowyouhavethefinalsay.

D.Keepgivingorderstoeveryone.

36.SectionB

Directions:Inthissection,youwillhear3shortpassages.Attheendofeachpassage,youwillhearsomequestions.Boththepassageandthequestionswillbespokenonlyonce.Afteryouhearaquestion,youmustchoosethebestanswerfromthefourchoicesmarkedA,B,CandD.

听力原文：WhenJohnWilton,writerofParadiseLost,enteredCambridgeUniversityin1695,hewasalreadyskilledinLatinaftersevenyearsofstudyingitashissecondlanguageatSt.Paul'sschool,London.LikeallEnglishboyswhopreparedforcollegeingrammarschool,hehadlearnednotonlytoreadLatinbutalsotospeakandwriteitfluentlyandcorrectly.HispronunciationofLatinwasEnglish,however,andseemedtohavesoundedstrangetohisfriendswhenhelatervisitedItaly.

SchoolboysgainedtheirskillinLatinthehardway.Theymemorizedrulestomakelearningbyhearteasier,TheyfirstmadeawordforwordtranslationandthenanidiomatictranslationintoEnglish.Astheyincreasedtheirskill,theytranslatedtheirEnglishbackintoLatinwithoutreferringtothebookandtheycomparedtheirtranslationwiththeoriginal.Theschoolmasterwasalwaysathandtoencouragethem.AllschoolmastersbelievedLatinshouldbebeatenin.Afterseveralyearsofstudy,theboysbegantowritecompositionsinimitationoftheLatinwriterstheyread.AndastheybegantoreadLatinpoems,theybegantowritepoemsinLatin.

BecauseMiltonwasalreadyapoetatten,hispoemsweremuchbetterthanthosepainfullyputtogetherbyotherboysDuringthesevenyearsMiltonspentattheuniversity,hemadeconstantuseofhiscommandofLatin.HewrotesomeexcellentLatinpoemswhichhepublishedamonghisworksin1645.

(27)

A.HowJohnMiltonWroteParadiseLost.

B.HowJohnMiltonBecameaPoet.

C.HowJohnMiltonStudiedLatin.

D.HowJohnMiltonBecameFamous.

37.听力原文：W:Hi．Ihaveamapofthecampus，butIstillcan'tfindthebuildingwiththenewlibraryinit．Canyoutellmehowtogetthere?

M:That'sbecauseit'sanoldmap．Followme,I'mgoingthatwaymyself．

Q:Whatdoesthemanmean?

(14)

A.Heknowswheretogetanewmap.

B.Hewillhelpthewomanreadthemap.

C.Hehasalreadyseenthelibrary.

D.Hewillgotothelibraryaswell.

38.

【B8】

39.(43)

40.(32)

A.Becausewecansucceedonlybymakingmistakes.

B.Becauseitisnecessaryforustomakemistakesifwewanttobesuccessful.

C.Becausemakingmistakesmeansgivingusmoreusefulknowledge.

D.Becauseallthebookknowledgeisgainedbymakingmistakes.

三、4.ReadingComprehension(ReadinginDepth)(20题)41.

TheNewYorkKnicksrecoveredfrom______tobecomeamajorcontenderinthe1980s.

42.Whatisthepoliticalimplicationofthedemographicchangeinthedevelopedcountries?

A.Winningthesupportofolderpeoplewillbecomecrucialinpolitics.

B.Pensionpolicywillbecomeakeyissueinelections.

C.Immigrationshouldbebannedtomaintaintheworkforce.

D.Thedemographicchangewillchangethepoliticallandscapegreatly.

43.TheBritish,DutchandGermangovernmentswillpre-financeIcelandsothatitcanmeetits______withinashortperiodoftime.

44.

Laughtercanbeawayofbodyexerciseifpeople______.

A.laughmuchmorethantheydoineveryday

B.laughmuchlouderthantheydoineveryday

C.receivespecialtraininginhowtolaugh

D.learntolaughwhiledoingotherexercises

45.SectionA

Directions:Inthissection,thereisashortpassagewith5questionsorincompletestatements.Readthepassagecarefully.Thenanswerthequestionsorcompletethestatementsinthefewestpossiblewords.

InthefirstyearorsoofWebbusiness,mostoftheactionhasrevolvedaroundeffortstotaptheconsumermarket.Morerecently,astheWebprovedtobemorethanafashion,companieshavestartedtobuyandsellproductsandserviceswithoneanother.Suchbusiness-to-businesssalesmakesensebecausebusinesspeopletypicallyknowwhatproductthey'relookingfor.

Nonetheless,manycompaniesstillhesitatetousetheWebbecauseofdoubtsaboutitsreliability."Businessesneedtofeeltheycantrustthepathwaybetweenthemandthesupplier",sayssenioranalystBlancErwinofForresterResearch.Somecompaniesarelimitingtheriskbyconductingonlinetransactionsonlywithestablishedbusinesspartnerswhoaregivenaccesstothecompany'sprivateintranet.

AnothermajorshiftinthemodelforInternetcommerceconcernsthetechnologyavailableformarketing.Untilrecently,Internetmarketingactivitieshavefocusedonstrategiesto"pull"customersintosites.Inthepastyear,however,softwarecompanieshavedevelopedtoolsthatallowcompaniesto"push"informationdirectlyouttoconsumers,transmittingmarketingmessagesdirectlytotargetedcustomers.Mostnotably,thePointcastNetworkusesascreensavertodeliveracontinuallyupdatedstreamofnewsandadvertisementstosubscribers'computermonitors.Subscribers(订购者)cancustomizetheinformationtheywanttoreceiveandproceeddirectlytoacompany'sWebsite.CompaniessuchasVirtualVineyardsarealreadystartingtousesimilartechnologiestopushmessagestocustomersaboutspecialsales,productofferings,orotherevents.ButpushtechnologyhasearnedthecontemptofmanyWebusers.Onlineculturethinkshighlyofthenotionthattheinformationflowingontothescreencomestherebyspecificrequest.Oncecommercialpromotionbeginstofillthescreenuninvited,thedistinctionbetweentheWebandtelevisionfades.That'saprospectthathorrifiesNetpurists.

ButitishardlyinevitablethatcompaniesontheWebwillneedtoresorttopushstrategiestomakemoney.TheexamplesofVirtualVineyards,A,andotherpioneersshowthataWebsitesellingtherightkindofproductswiththerightmixofinteractivity,hospitality,andsecuritywillattractonlinecustomers.Andthecostofcomputingpowercontinuestofreefall,whichisagoodsignforanyenterprisesettingupshopinsilicon.Peoplelookingback5or10yearsfromnowmaywellwonderwhysofewcompaniestooktheonlineplunge.

WelearnfromthebeginningofthepassagethatWebbusinesshasbeenstrivingtoexpandits______.

46.

Now,themosteffectiveform.ofadvertisingis______.

A.a30-secondprime-timeTVad

B.a30-secondprime-timeonlineadvertising

C.onlineadvertising

D.mostexpensiveTVad

47.

Whydopeoplefeelsqueezedwhentheiraverageincomerisesconsiderably?

A.Theirmaterialpursuitshavegonefaraheadoftheirearnings.

B.Theirpurchasingpowerhasdroppedmarkedlywithinflation.

C.Thedistributionofwealthisunevenbetweentherichandthepoor.

D.Healthcareandeducationalcostshavesomehowgoneoutofcontrol.

48.Nestleandsomebottledwatercompaniesaretryingtoreducetheenvironmentalimpactbyshiftingto

49.

WhichofthefollowingartistspioneeredCubistart?

A.Cezanne.B.Picasso.C.Michelangelo.D.Anunknownartist.

50.SectionA

Directions:Inthissection,thereisapassagewithtenblanks.Youarerequiredtoselectonewordforeachblankfromalistofchoicesgiveninawordbankfollowingthepassage.Readthepassagethroughcarefullybeforemakingyourchoices.Eachchoiceinthebankisidentifiedbyaletter.Pleasemarkthecorrespondingletterforeachitemwithasinglelinethroughthecenter.Youmaynotuseanyofthewordsinthebankmorethanonce.

Forestisacomplexecosysteminwhichtreesarethedominantlifeform.Treedominatedforestscanoccurwhereverthetemperaturesriseabove50°F(10℃)inthewarmestmonthsandtheannual【C1】______ismorethan8in.(200mm).Theycandevelopundervariousconditionswithintheselimits,andthekindofsoil,plant,andanimallifediffersaccordingtotheextremesofenvironmentalinfluences.Incool,high-latitudesubpolarregions,taigaforestsaredominatedby【C2】______conifers(针叶松).Inmoretemperatehigh-latitudeclimates,mixedforestsofbothconifersandbroad-leaveddeciduoustrees【C3】______.Broad-leaveddeciduousforestsdevelopinmidlatitudeclimates.Inhumidequatorialclimates,tropicalrainforestsdevelop.Thereheavyrainfallsupportsevergreensthathavebroadleavesinsteadoftheneedleleavesofcoolerevergreenforests.Forestsareamongthemostcomplexecosystemsintheworld,withextensiveverticallayering.Coniferforestshavethesimpleststructure:atreelayer,ashrublayerthatis【C4】______orevenabsent,andagroundlayercoveredwithlichens,mosses,andliverworts.Deciduousforestsaremorecomplex(thetreecanopyisdividedintoanupperandlowerstory),andrain-forestcanopiesaredividedintoatleastthreelayers.Theforestisnature'smostefficientecosystem,withahighrateof【C5】______affectingbothplantandanimalsystemsincomplexorganicrelationships.

Rainforestislushforest,generallycomposedoftall,broad-leavedtreesandusuallyfoundinwettropicalregionsaroundtheequator.Dependingontheamountofannualrainfall,thetreesmaybeevergreensormainlydeciduous.Theformerrequiremorewater.Soilconditionsvarywithlocationandclimate,thoughmostrain-forestsoilstendtobepermanentlymoistandnotvery【C6】______,becausethehot,humidweathercausesorganicmattertodecomposerapidlyandtobeabsorbedquicklybytreerootsandfungi.Rainforestshavemanyverticallayersofplantandanimaldevelopment.Thehighestplantlayer,thetreecanopy,【C7】______toheightsof100-165ft(30-50m).Animalstheremostlyfeedandescapefrompredatorsamongleavesandbranches.Thenext-highestlayerisfilledwithsmalltrees.Abovethegroundsurfacethespaceisoccupiedbytreebranches,twigs,and【C8】______.Manyspeciesofanimalsliveintheundergrowth.Contrarytopopularbelief,therainforestfloorisnotimpassable,beingbareexceptforathinlayerofhumusandfallenleaves.Animals【C9】______thislayerareadaptedtowalkingandclimbingshortdistancesBurrowinganimalsarefoundbelowthesoilsurface,asaremicroorganismsthathelpdecomposeandfreemuchoftheorganiclitteraccumulatedbyotherplantsandanimalsfromalllayers.Theclimateofthegroundlayerisunusually【C10】______becausetheupperstoriesoftreecanopiesandthelowerbranchesfiltersunlightandheatradiationandreducewindspeeds,keepingthetemperaturesfairlyeven.

A.resortI.extends

B.stableJ.inhabiting

C.conformK.predominate

D.foliageL.biology

E.fertileM.spotty

F.apprenticeN.precipitation

G.photosynthesisO.perishing

H.hardy

【C1】

51.AscivilwarseruptedthroughouttheRomanRepublicinthe1stcenturyB.C.,countrydwellersmayhavefledtocities.Beforetheyleft,somepeopleburiedtheirvaluablestohidethemfromarmies.Nowsocialscientistshavestudiedthesecoinstorestoansweralong-standingRomanmystery.

HistorianshavelongdebatedRome'sp