六级模拟一.docx

六级模拟一.docx

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六级模拟一

PartIWriting（30minutes）

　　Directions:

Forthispart,youareallowed30minutestowriteashortessayentitledSayNotoPiratedProducts.Youshouldwriteatleast150wordsfollowingtheoutlinegivenbelow。

　　1.目前盗版的现象比较严重；

　　2.造成这种现象的原因及其危害；

　　3.我们应该怎么做。

　　Usefulwordsandexpressions：

　　盗版：

piracy（n。

）

　　盗版产品：

piratedproducts

　　知识产权：

intellectualpropertyrights

　　侵犯版权：

infringesb.'scopyright；copyrightinfringement

　　PartⅡReadingComprehension（SkimmingandScanning）（15minutes）

　　Directions:

Inthispart,youwillhave15minutestogooverthepassagequicklyandanswerthequestionsontheAnswerSheet。

　　ForquestionsI-4,mark

　　Y（forYES）ifthestatementagreeswiththeinformationgiveninthepassage;

　　N（forNO）ifthestatementcontradictstheinformationgiveninthepassage;

　　NG（forNOTGIVEN）iftheinformationisnotgiveninthepassage。

　　Forquestions5-10,completethesentenceswiththeinformationgiveninthepassage。

　　Rainforests

　　Tropicalrainforestsarethemostdiverseecosystem（生态系统）onEarth,andalsotheoldest.Today,tropicalrainforestscoveronly6percentoftheEarth'sgroundsurface,buttheyarehometooverhalfoftheplanet’splantandanimalspecies。

　　WhatIsaRainforest?

　　Generallyspeaking,arainforestisanenvironmentthatreceiveshighrainfallandisdominatedbytalltrees.Awiderangeofecosystemsfallintothiscategory,ofcourse.Butmostofthetimewhenpeopletalkaboutrainforests,theymeanthetropicalrainforestslocatedneartheequator。

　　Theseforestsreceivebetween160and400inchesofrainperyear.Thetotalannualrainfallisspreadprettyevenlythroughouttheyear,andthetemperaturerarelydipsbelow60degreesFahrenheit。

　　Thissteadyclimateisduetothepositionofrainforestsontheglobe.BecauseoftheorientationoftheEarth'saxis,theNorthernandSouthernhemisphereseachspendpartoftheyeartiltedawayfromthesun.Sincerainforestsareatthemiddleoftheglobe,locatedneartheequator,theyarcnotespeciallyaffectedbythischange.Theyreceivenearlythesameamountofsunlight,andthereforeheat,allyear.Consequently,theweatherintheseregionsremainsfairlyconstant。

　　Theconsistentlywet,warmweatherandamplesunlightgiveplantlifeeverythingitneedstothrive.Treeshavetheresourcestogrowtotremendousheights,andtheyliveforhundreds,eventhousands,ofyears.Thesegiants,whichreach60to150ftintheair,formthebasicstructureoftherainforest.Theirtopbranchesspreadwideinordertocapturemaximumsunlight.Thiscreatesathickcanopy（树冠）levelatthetopoftheforest,withthinnergreenerylevelsunderneath.Somelargetreesgrowsotallthattheyeventoweroverthecanopylayer。

　　Asyougolower,downintotherainforest,youfindlessandlessgreenery.Theforestfloorismadeupofmoss,fungi,anddecayingplantmatterthathasfallenfromtheupperlayers.Thereasonforthisdecreaseingreeneryisverysimpletheoverabundanceofplantsgatheringsunlightatthetopoftheforestblocksmostsunlightfromreachingthebottomoftheforest,makingitdifficultforrobustplantstothrive。

　　The,ForestfortheTrees

　　Theamplesunlightandextremelywetclimateofmanytropicalareasencouragethegrowthoftoweringtreeswithwidecanopies.Thisthicktoplayeroftherainforestdictatesthelivesofallotherplantsintheforest.Newtreeseedlingsrarelysurvivetomakeittothetopunlesssomeoldertreesdie,creatinga"hole"inthecanopy.Whenthishappens,alloftheseedlingsonthegroundlevelcompeteintenselytoreachthesunlight。

　　Manyplantspeciesreachthetopoftheforestbyclimbingthetalltrees.Itismucheasiertoascendthisway,becausetheplantdoesn'thavetoformitsownsupportingstructure。

　　Someplantspecies,calledepiphytes,growdirectlyonthesurfaceofthegianttrees.Theseplants,whichincludeavarietyoforchidsandferns,makeupmuchoftheunderstory,thelayeroftherainforestrightbelowthecanopy.Epiphytesarecloseenoughtothetoptoreceiveadequatelight,andtherunofffromthecanopylayerprovidesallthewaterandnutrients（养分）theyneed,whichisimportantsincetheydon'thaveaccesstothenutrientsintheground。

　　StranglersandButtresses

　　Someepiphyteseventuallydevelopintostranglers.Theygrowlong,thickrootsthatextenddownthetreetrunkintotheground.Astheycontinuetogrow,therootsformasortofwebstructureallaroundthetree.Atthesametime,thestranglerplant'sbranchesextendupward,spreadingoutintothecanopy.Eventually,thestranglermayblocksomuchlightfromabove,andabsorbsuchahighpercentageofnutrientsfromthegroundbelow,thatthehosttreedies。

　　Competitionovernutrientsisalmostasintenseascompetitionforlight.Theexcessiverainfallrapidlydissolvesnutrientsinthesoilmakingitrelativelyinfertileexceptatthetoplayers.Forthisreason,rainforesttreerootsgrowoutwardtocoverawiderarea,ratherthandownwardtolowerlevels.Thismakesrainforesttreessomewhatunstable,sincetheydon'thaveverystronganchorsintheground.Sometreescompensateforthisbygrowingnaturalbuttresses.Thesebuttressesarebasicallytreetrunksthatextendoutfromthesideofthetreeandclowntotheground,givingthetreeadditionalsupport。

　　Rainforesttreesaredependentonbacteriathatarecontinuallyproducingnutrientsintheground.Rainforestbacteriaandtreeshaveaveryclose,symbiotic（共生的）relationship.Thetreesprovidethebacteriawithfood,intheformoffallenleavesandothermaterial,andthebacteriabreakthismaterialdownintothenutrientsthatthetreesneedtosurvive。

　　Oneofthemostremarkablethingsaboutrainforestplantlifeisitsdiversity.ThetemperaterainforestsofthePacificNorthwestaremainlycomposedofadozenorsotreespecies.Atropicalrainforest,ontheotherhand,mighthave300distincttreespecies。

　　AllCreatures,GreatandSmall

　　Rainforestsarehometothemajorityofanimalspeciesintheworld.Andagreatnumberofspecieswhonowliveinotherenvironments,includinghumans,originallyinhabitedtherainforests.Researchersestimatethatinalargerainforestarea,theremaybemorethan10milliondifferentanimalspecies。

　　Mostofthesespecieshaveadaptedforlifeintheupperlevelsoftherainforest,wherefoodismostplentiful.Insects,whichcaneasilyclimborflyfromtreetotree,makeupthelargestgroup（antsarethemostabundantanimalintherainforest）.Insectspecieshaveahighlysymbioticrelationshipwiththeplantlifeinarainforest.Theinsectsmovefromplanttoplant,enjoyingthewealthoffoodprovidedthere.Astheytravel,theinsectsmaypickuptheplants'seeds,droppingthemsomedistanceaway.Thishelpstodispersethepopulationoftheplantspeciesoveralargerarea。

　　Thenumerousbirdsoftherainforestalsoplayamajorpartinseeddispersal.Whentheyeatfruitfromaplant,theseedspassthroughtheirdigestivesystem.Bythetimetheyexcrete（排泄）theseeds,thebirdsmayhaveflownmanymilesawayfromthefruit-bearingtree。

　　Therearealsoalargenumberofreptilesandmammalsintherainforest.Sincetheweatherissohotandhumidduringtheday,mostrainforestmammalsareactiveonlyatnight,duskordawn.Themanyrainforestbatspeciesareespeciallywelladaptedforthislifestyle.Usingtheirsonar,batsnavigateeasilythroughthemassoftreesintherainforest,feedingoninsectsandfruit。

　　Whilemostrainforestspeciesspendtheirlivesinthetrees,thereisalsoalotoflifeontheforestfloor.Greatapes,wildpigs,bigcatsandevenelephantscanallbefoundinrainforests.Thereareanumberofpeoplewholiveintherainforests,aswell.Thesetribes--which,upuntilrecently,numberedinthethousands--arebeingforcedoutoftherainforestsatanalarmingratebecauseofdeforestation。

　　Deforestation

　　Inthepasthundredyears,humanshavebegundestroyingrainforestsatanalarmingrate.Today,roughly1.5acresofrainforestaredestroyedeverysecond.Peoplearecuttingdowntherainforestsinpursuitofthreemajorresources:

　　·landforcrops

　　·lumberforpaperandotherwoodproducts

　　·landforlivestockpastures

　　Inthecurrenteconomy,peopleobviouslyhaveaneedforalloftheseresources.Butalmostallexpertsagreethat,overtime,wewillsuffermuchmorefromthedestructionoftherainforeststhanwewillbenefit。

　　Theworld'srainforestsareanextremelyvaluablenaturalresource,tobesure,butnotfortheirlumberortheirland.TheyarethemaincradleoflifeonEarth,andtheyholdmillionsofuniquelifeformsthatwehaveyettodiscover.Destroyingtherainforestsiscomparabletodestroyinganunknownplanetwehavenoideawhatwe'relosing.Ifdeforestationcontinuesatitscurrentrate,theworld'stropicalrainforestswillbewipedoutwithin40years。

　　1.VirtuallyallplantandanimalspeciesonEarthcanbefoundintropicalrainforests。

　　2.Thereisnotmuchchangeintheweatherinthetropicalrainforestsalltheyearround。

　　3.ThelargestnumberofrainforestsintheworldarelocatedontheAfricancontinent。

　　4.Belowthecanopylevelofatropicalrainforestgrowsanoverabundanceofplants。

　　5.Newtreeseedlingswillnotsurvivetoreachthecanopylevelunless______。

　　6.Epiphytes,whichformmuchoftheunderstoryoftherainforest,getalltheirwaterandnutrientsfrom______。

　　7.Stranglersaresocalledbecausethey______byblockingthesunlightandcompetingforthenutrients。

　　8.Sincerainforestbacteriaandtreesdependoneachotherforlife,therelationshiptheyformistermed______。

　　9.Plantspeciesaredisperse