冲刺阅读精读团1711讲义

3A逻辑考点精读团第46期【请密切留意讲座课程通知】请关公 个 ： 期精读团】 间及安第一次课【月日】:30-22:00—P1第二次课【11月9日】19:30-22:00—P2+P3文章精读讲解第三次课【111219:30-22:00—P4P5第四次课【111419:30-22:00—P6P7课在YY语音上课，请宝宝们提前准备好电脑先YY语音软件→安装之后→账号→登录→改YY昵称号码 昵称)→在软件右上角输入频道【8683】→按ENTER键进入频*点击左下角教室列表选择【 11月精读团】子频道→频道见QQ群a)570词汇书（《570个单词轻松征服托福》；当当网亚马逊京东都可以买到）；不管你之前背了多少词汇，570是我们精读团的词汇基础，必须要熟练掌握【阅读全词霸营宣讲会+5 /s/1bprpf0V：sdqa /s/1mi9nBVM第一次课后会发单项课（包括句子简化题）的答案到QQ群文件。201711【P1】MatingSongsof【P2】ClimateChangeandtheNatufian【P3】FarmingNewEnglandinColonial【P4】TheClimateof【P5】ArchitrcturalChangeinEighth-Century【P7】Bisonand【P8】ArtisansinSixteenth-Century【P10】IndividualPerformanceandthePresencef【P1MatingSongsofThecallingorsingingysanimportantroleintheirreproduction-specifically,inhelindividualsfindandselectmates.Soundhasmanyadvantagesasacommunicationsignal.Whensoundsarebroadcast,theauditoryreceptorsdonotneedtobeinaparticularorientationrelativetothesoundsourceinordertoreceivestimulation.Loudsongs,particularlythosemadebychorusesofcallingtogether,cantravellongdistancesandthusattractdistant.Soundstravelaroundlargeobstacles.Theseadvantagesarenotfoundinthevisualmodality,wherethereceivermustbeattentiveandhaveitsvisualreceptororientatedinthecorrectdirection.Further,mostandtoadsbreedatnight,whenlightlevelsarelowbutsoundscanbeeasilylocalized.Wecanconcludethatauditorysignalsareusedbyandtoadsbecausetheycanbeeffectiveoverlongdistancesatnight.Maledomostofthecourtshipcalling.Othermalecanrespondbyaddingtheirvoicestoformacallingchorus.Malecanalsovocalizetoeachotheraspartofaggressivedisys.Aggressivecallscanbedistinctfromtheadvertisementcallsusedtoatractfemales.Femalescanrespondtomalesongsbymovingtowardthesoundsourceorbyselectingcertainmalesasreproductivepartners.Insomespeciesfemalesalsorespondtomalesbycalling:receptivepairscanevenperformduets.Predatorsmayalsocueinoncallingaspotentialprey.Frogsongscontainseveralpotentiallyimportantpiecesofinformationaboutthecallingmale.First,soundamplitudecanindicatethesizeoftheindividualthatiscalling.Sincemanyexhibitindeterminategrowth(i.e.Theykeepgettingbiggerastheygetolder),sizeisagoodpredictorofrelativeage.Inmanyspecies,callamplitudeisincreasedbyspecializedvocalsacsthatcanenlargeastheanimalgrows;thus,olderproduceloudercalls.Themale’sagematterstothefemalebecauseolderhavesucessfullysurvivedtheenvironmentalhazardsthattheoffspringtheysirewillsoonbefacing.Amplitudecanasoconveyinformationonhowfarawaythecallingisor,forchoruseshowmanyarecallingtogether.Anintenselyvocalizingchorusmayindicateaparticularlyfavorablebreedingsite.Soundamplitude(subjectively:loudness)canbeanambiguouscueforafemale,however.Averyintensesoundcanindicateanoldmateatsomedistanceorayoungermalethatisclose.Aclose,smallchoruscouldbeconfusedwithalouderchorusthatisfartheraway.Soundfrequencies-orpitch-canalsoconveyinformationaboutthecallingmalebecausethevocalapparatusgrowslargerasthefroggrowsolder.■Insome,thepitchofindividualsoundsvarieswithage,sothatolderandlargermalesgivelower-pitchedcalls.■Soundpitchisaffectedbytemperature;smallmalescanmimicthelowerpitchoflarger,oldermalesbycallingfromcolderlocations.■Finally,thelengthoftimethatanindMcanaffordtospendcallingisagoodindicatorofhishealth.Manyinvestconsiderableenergyincalling,bothbecausetheydonotfeedandbecauseitisaphysicallydemandingbehaviorthatreliesonrapidmuscularcontractionsofthevocalizationapparatus.Thiseffortcanbedebilitatinginamalefrogthatisnotintopphysicalcondition.Callingintreeissaidtobethemostenergeticallyexpensivebehavioryetmeasuredanyvertebrate.Soundfrequenciesandtheovealltmporalpattern(rhythmandrate)ofthesongcanalsorevealthespeciesofthecallingmale.Thefrequenciesoffrogsoundsandtheirtemporalpatternsarespecies-specific.Thespeciesofapotentialmateisextremelyimportanttothefemale.Femalesthatchoosetomatewithmembersofanotherspeciesrisklosingtheenergyinvesteggsbecausethehybridoffspringwillnotsurviveandreproduce.Thecomplexityofafrogsongcanalsoaffecthowattractiveitistoafemale.Thesongsofmaletungara,forexample,canconsistsimplyofshorthigh-frequency”whines”orbyseverallower-frequency“chucks”.Morefemalesapproachloudspeakersyingwhinespluschucksthanwhinesalone.Theadditionofchucks,however,alsohasthedisadvantageofattractingbatsthateatthe.Accordingtoparagraph1,allofthefollowingarementionedastrueofthematingcallsofTheycanreachinfar-offTheyarenotblockedbyobjectsofsubstantialTheyareoftencombinedwithnonauditoryTheycanbereceivedwithoutthefrog’sneedingtoorientitselftowardthedirectionoftheTheauthorprovidesinformationabout“thevisualmodality”inorderEmphasizethatvisualinformationysasignificantpartinfrogExinwhysomebreedatnight.WhileothersbreedduringtheindicatetheresourcefulnesswithwhicheobstaclesinsoundtravelduringthebreedingDarguethatauditorysignalshaveadvantageovervisualsignalsforfrogTheword“potential”inthepassageisclosestinmeaningTheword“favorable”inthepassageisclosestinmeaningwellAccordingtoparagraph3,femalewholistentofrogsongsaretryingtodeterminewhetherafuturecanprotectfutureoffspringfromhasanimportantsocialpositionwithinthemalehasreachedanagethatindicatestheabilitytosurviveenvironmentalisyoungenoughtobeabletoproducemanyItcanbeinferredfromparagraph3thatfemaleareseekingmatescaninhabitavarietyofbreedingcanoccupyhabitatsatadistancefromthoseofyoungermalehaveprotectedpreviousmatesfromenvironmentalarelikelytopassontraitsthatstrengthentheiroffspring’schancesofTheword“ambiguous”inthepassageisclosestinmeaningTheword“convey”inthepassageisclosestinmeaningaddParagraph4impliesthatyoungmaycallfromcoldareasforwhichofthefollowingToindicatesuperiorstrengthoveroldermToappearmoreattractivetofemalesbysoundingoderthanactuallyobeabletospendlessenergyinproducingtheirTocompeteagainstfewermalesforafemale’sInparagraph4,whydoestheauthormentionthattreefrogcallingissaidtobe“themostexpensivebehavioryetmeasuredinanyToexinwhyitisimportantfortreetobeintopphysicalTodistinguishtreefromotherspeciesofToindicatethatsurvivalismoredifficultforthanforotherToemphasizehowmuchphysicaleffortcallingItcanbeinferredfromparagraph5thathavingspeciesspecificsongsbenefitsinwhichofthefollowingways?ItenablestobetterprotecteggsfrombeingdamagedbymembersofotherItmakesitpossiblefortojudgetheirdistancefrompotentialIthelpstoavoidhavingoffspringthatcannotsurviveandItmakesitpossiblefortoinvestmoreoftheirenergyintoproducingAccordingtoparagraph6,tungaraaddachucksoundtotheircallinordermakethemselvesmoreattractivetokeeppredatorsatasafeattractiveofdifferentincreasetheloudnessoftheirSoundfrequencies-orpitch-canalsoconveyinformationaboutthecallingmalebecausethevocalapparatusgrowslargerasthefroggrowsolder.■Insome,thepitchofindividualsoundsvarieswithage,sothatolderandlargermalesgivelower-pitchedcalls.■Soundpitchisaffectedbytemperature;smallmalescanmimicthelowerpitchofarger,oldermalesbycallingfromcolderlocations.■Finally,thelengthoftimethatanindMcanaffordtspendcallingisagoodindicatorofhishealth.Manyinvestconsiderableenergyincalling,bothbecausetheydonotfeedandbecauseitisaphysicallydemandingbehaviorthatreliesonrapidmuscularcontractionsofthevocalizationapparatus.Thiseffortcanbedebilitatinginamalefrogthatisnotintopphysicalcondition.Callingintreeissaidtobethemostenergeticallyexpensivebehavioryetmeasuredanyvertebrate.LookatthefoursquaresXthatindicatewherethefollowingsentencecouldbeaddedtotheButafrog’sageisnottheonlyinfluenceonthepitchofafrog’sWherewouldthesentencebestDirections:AnintroductorysentenceforabriefsummaryofthepassageisprovidedbelowCompletethesummarybyselectingtheTHREEanswerchoicesthatexpressthemostimportantideasinthepassage.Somesentencesdonotbelonginthesummarybecausetheyexpressideasthatarenotpresentedinthepassageorareminorideasinthepassage.Thisquestionisworth2points.ThecallingorsingingofisaformofForandtoads,soundhasanumberofadvantagesovervisualsignalsasamediumofcommunicationoverlongdistancesatnight.Callingisperformedprimarilybymaletoattractmatesforreproductionandtoactivelycompetewithothermaleforfemales.Dependingonthespecies,femalecanobtaininformationfromamale’ssongaboutage,health,andspeciesofthecaller.InsomespeciesbothmalesandfemalesproducematingsongseitherasIndividualpairsoraschoruses,thoughthechorusesarelikelytoattractPredators.FrogcallsaredifficulttointerpretbecauseoldandyounginCoolcesproducethesamesong,andnearthatareoldandweakcansoundlikefityoungcallingfromadistance.Becausecallingissuchatiringactivityfor,itisusedtocommunicateonlyaboutbiologicallynecessaryactivitiesandofteningroupsthatdistributethecallingeffortamongmanyindividual.【P2】ClimateChangeandtheNatufianTheso-calledNatufiancultureinhabitedwhatisnowtheMiddleEastbetweenapproximay14,000and11,500yearsago.Thisperiodiscommonlysplitintotwosubperiods,EarlyNatufian(14,000to13,000yearsago)andLateNatufian(13,000to11,500).TheNatufianswerehunter-gathererswhoreliedprimarilyongazelle,althoughtheyalsocultivatedsomecerealgrains.Duringtheearlyperiodatleast,theylivedyear-roundinvillagesinbuiltstonehouses.Likeallhumanbeings,theirwayoflifedependedontheclimate.Around13,000yearsago,theirclimatebegantochange, ingcolderanddrier,aperiodknownastheYoungerDryas.WeknowthattimeswerehardintheincreasinglyaridlandscapesoftheYoungerDryas,butquitehowhardremainsunclear.Thedroughtscertainlycausedmanypondsandriverstodisappearcompleyandthelargerlakestoshrinkinsize.Thepeoplewholivedinthesouth,intoday’sdesertsoftheNegevandtheSinai,weremostlikelyhitthehardest.Theyreturnedtoacompleytransienthunter-gathererwayoflife,movingfromcetoce.Survivalrequiredimprovedhuntingweapons:game(animalshuntedforfood)had escarce,andconsequently,successhad eessentialwhenakillwaspossible.AndsoweseetheinventionoftheHarifpoint,anewkindofarrowhead.Furthernorth,theimpactoftheYoungerDryasmayhavebeenlesssevereYetsurvivalstillrequiredmorethanjustareturntotheancienthunter-gathererlifestyle,especiallyastherewerenowmanymorepeopleneedingfoodthanhadbeenthecaseduringearlierperiods,whentheNatufianslivedinpermanentdwellings.Oneresponsewastohuntamuchwiderrangeofanimalsthanbefore,andhencewefindinLateNatufiansettlementsthebonesofmanysmall-gamespeciesaswellaslarger,ever-presentgazelleAnotherresponsetothechangingclimatewastocontinue,andperhapsexpandthecultivationofntsWildcerealswereparticularlyhardhitbytheYoungerDryasowingtoadecreaseintheconcentrationofcarbondioxide(CO2)intheatmosphere.Thisdiminution,carefullyedfromairbubblestrappedinAntarctiiceinhibitedtheirphotosynthesisandmarkedlyreducedtheiryields.Consequently,whatevercultivationpracticeshadbegunduringtheEarlyNatufianperiod—weeding,transnting,watering,pestcontrol—maynowhaveeessentialtosecuresufficientfood.AndthesemayhavecreatedthefirstdomesticatedThisappearstobewhathappenedatthevillageofAbuHureyrajustbeforeitsabandonment.WhenthearchaeologistGordonHillmanstudiedthecerealgrainsfromthesite,hefoundafewgrainsofryefromntsthathadundergonethetransitionintodomesticforms.Whendated,theywereshowntoliebetween11,000and10,500B.C.—theoldestdomesticatedcerealgrainfromanywhereintheworld.Alongwiththesegrains,Hillmanfoundseedsfromtheweedsthattypicallygrowincultivatedsoil.Andsoitappearsthat,astheavailabilityofwildntfoodsdeclinedduetotheonsetoftheYoungerDryas,theAbuHureyrapeopleinvestedanevergreateramountoftimeandeffortincaringforthewildryeandbyngsounintentionallytransformeditintoadomesticcropButeventhiscouldnotsupportthevillage—itwasabandonedaspeopleweredtoreturntoalifestyleperhapscarryingpouchesofcerealgrain.ThedomesticatedryeofAbuHureyrarevertedtoitswildstate.ThegeographicalrangeoftheLateNatufiansalsochanged.Withtheirincreasedinterestinntcultivation,theLateNatufiansdriftedawayfromthedepletedwoodlandswheretheirforebearsonceflourished.Theyweredrawntothealluvialsoils(solsdepositedbyrivers)ofthevalleys,notonlythoseoftheRiverJordan,butalsothosefoundbythegreatriversoftheMesopotamianinandinthevicinityoflakesandriversthroughouttheMiddleEast.LargeexpansesoftheserichfertiesoilsbecameavailableastheriversandlakesstruckduringtheYoungerDryasWild,butcultivated,cerealsgrewwellinsuchsoil,especiallywhenclosetothemeagersprings,ponds,andstreamsthatsurvivedthearidconditons.Whichofthefollowingcanbeinferredfromparagraph2aboutwhygamebecamescarceduringtheYoungerHumansettlementinthesouthdestroyedtheresourcesthatallowedgameanimalstoAnimalsdiedormovedawayastheirsourcesofdrinkingwaterdriedAnimalswerescaredawaybytheNatufians’rapidmovementfromcetoInparagraph2,whydoestheauthormentiontheHarifAccordingtoparagraph3,whatdidtheNatufiansdotofeedtheirincreasingpopulationduringtheYoungerTheybeganhuntingawiderrangeofTheytriedtohuntmostlythelargerTheymovedsouthwherethereweremoreAccordingtoparagraph4,airbubblesinAntarcticiceareevidenceofwhichofthefollowingduringtheYoungerDryasperiod?AnincreaseinthenumberofGreateruseofpestTheword“inhibited”inthepassageisclosetinmeaningTheword“sufficient”inthepassageisclosetinmeaningInparagraph5,whydoestheauthordescribedthearchaeologist’sfindingsatAbuTochallengetheideapresentedinpaagraph4thatearliercultivationpracticesbecameessentialforNatufiansurvivalduringtheYoungerDryasToprovideevidencesupportingthetheorypresentedinparagraph4abouthowwildntsbecameAccordingtoparagraph5,whatwasoneresponseofthepeopleofAbuHureyratotheonsetoftheYoungerTheybegancollectingawidervarietyofwildTheybegancultivatingcropsatsitesoutsideAbuTheyspentmoreenergyandtimecultivatingtheirryeItbecamewildItbecameItcouldnolongerbeusedasTheword“flourished”inthepassageisclosetinmeaningThephrase“drawnto”inthepassageisclosetinmeaningntsgrewbetterinthefertilesoilnexttobodiesofTheNatufiansusedtheriversastheirmeansofTheso-calledNatufiancultureinhabitedwhatisnowtheMiddleEastbetweenapproximay14,000and11,500yearsago.Thisperiodiscommonlysplitintotwosubperiods,EarlyNatufian(14,000to13,000yearsago)andLateNatufian(13,000to11,500).TheNatufianswerehunter-gathererswhoreliedprimarilyongazelle,althoughtheyalsocultivatedsomecerealgrains.■Duringtheearlyperiodatleast,theylivedyear-roundinvillagesinbuiltstonehouses.Likeallhumanbeings,theirwayoflifedependedontheclimate.■Around13,000yearsago,theirclimatebegantochange, ingcolderanddrier,aperiodknownastheYoungerDryas.■WeknowthattimeswerehardintheincreasinglyaridlandscapesoftheYoungerDryas,butquitehowhardremainsunclear.■Thedroughtscertainlycausedmanypondsandriverstodisappearcompleyandthelargerlakestoshrinkinsize.Thepeoplewholivedinhesouth,intoday’sdesertsoftheNegevandtheSinai,weremostlikelyhitthehardest.Theyreturnedtoacompleytransienthunter-gathererwayoflife,movingfromcetoce.Survivalrequiredimprovedhuntingweapons:game(animalshuntedforfood)had escarce,andconsequently,successhad eessentialwhenakillwaspossible.AndsoweseetheinventionoftheHarifpoint,anewkindofarrowhead.Lookatthefoursquares[■]thatindicatewherethefollowingsentencecouldbeaddedtotheAslongastheclimateremainedmoderate,theNatufianswereabletothrivebyremainingintheirWherewouldthesentencebestfit?Clickonasquare[■]toaddthesentencetotheDirections:Anintroductorysentenceforabriefsummaryofthepassageisprovidedbelow.CompletethesummarybyselectingtheTHREEanswerchoicesthatexpressthemostimportantideasnthepassage.Someanswerchoicesdonotbelonginthesummarybecausetheyexpressideasthatarenotpresentedinthepassageorareminorideasinthepassage.Thisquestionisworth2points.Dragyourchoicestothespaceswheretheybelong.Toreviewthepassage,clickonViewAboutAbout13,000yearsago,acolderanddrierperiodknownastheYoungerDryascausedtheNatufianpeopletoaltertheirlifestyle.AnswerAslakesandriversdriedup,Natufiansabandonedtheirsettlementsinsomeareasandbecamehunters,develonew,moreefficienthuntingweaponstoimprovetheirsuccessinthehunt.Cerealyieldsdroppedwhentheairbecameexcessivelyconcentratedwithcarbondioxide,whichimpairedInoneNatufianvillage,anarchaeologistfoundtheoldest-knowndomesticatedcerealgrain,datingfrommorethan14,000yearsago.AmajorcontributionofNatufianculturetoearlycivilizationwastheinventionofanewarrowheadcalledtheHarifpoint.Withwildgrainsnolongerplentiful,theNatufianshadtoinventbettercultivationtechniques,resultinginnewdomesticatedvarieties.TheclimatechangedsomeLateNatufianstomoveawayfromtheirformerwoodlandhomesandinhabitthefertilelandsleftbytherecedingriversandlakes.【P3FarmingNewEnglandinColonialWhenintheseventeenthandeighteenthcenturiesEuropeansettlersarrivedinNewEngland,thenortheasternpartoftheUnitedStates,wasthedominantformofvegetativecover,makingagriculturedifficult.Initially,theEuropeanswentinsearchofareasalreadyclearedbyNativeAmericans(theoriginalinhabitantsofthecontinent)thatwouldbesuitableforntingcrops,totherebysavethemselvesfromthebackbreakinglaborinvolvedinclearingland.Eventually,however,populationgrowthoutstrippedthesupplyofclearedland,forcingtheEuropeansettlerstocutdownmorethemselves.Formostofthesettlers,cleared,arablelandwasthelandscapemostfamiliartothemfromlifebackacrosstheocanIttooktimeto eaccustomedtothehardlaborinvolvedincuttingdownthewoods.Inthenortherncolonies,treeswereusuallychoppeddown,althoughoccasionallyatechniqueknownasgirdlingwasused.Girdling,apracticefarmorecommonintheSouth,involvedcuttingahorizontalchannelallthewayaroundthetree,whichstoppedtheflowofsap,theliquidthatcarriesfoodtoallpartsofant.Deprivedofsap,theleaveswoulddieandthebrancheseventuallyfelloff,leavingthesurroundinglanddryandsuitableforNewEnglanders,however,generallyclear-cutthe,inpartbecausethedemandforfuelwoodandlumbermotivatedfarmerstocutandburnthewoods.Usedtomanufacturesoap,glass,andgunpowderandtolinensandprintcalicoes,potashservedarangeofindustrialusesbutattheexpenseoffarms,whichlostnutrientsthatthewoodasheswouldotherwisehavereleasedbackintothesoilhadtheynotbeenexportedWiththeirveryexistencedependentonthesuccessfulproductionoffood,farmershadlittle,ifany,timeforremovingstumpsandstones.Instead,theyadaptedtothehalf-clearedfieldsbyntingcorn(maize)andgrass;bothgrewwellinsuchanenvironment.Apatternofextensivefarmingbegantoemerge.Ratherthancarefullytendingarableland,engagingincroprotation,manuring,andremovingallstumpsandstones,allrecognizedaspartofproperagriculturalpracticeinEurope,NewEnglandfarmerssimplyexploitedthesoilandthenforgedaheadwiththeclearingofnewland.Cuttingdowntreesremainedhardwork,butitwaseasiertopartiallyclearthelandntit,andthenmoveontoanothersmallplotthantoconstantlyimprovethesoilononefieldtothehighOldWorld(European)standards.Thesettlersweretoobusyfiguringouthowtoproducefoodrapidlytoworryaboutefficientagriculturalpractices.Earlyon,thesettlersadoptedtheNativeAmericanpracticeofntingcornalongwithbeansandpumpkinsorsquash.Thesentsreindoneanotherresultinginhighagriculturalyields.Thestalksofcornfacilitatedthegrowthofbeansbygivingthemastructuretoclimb.Thebeansreplenishedthenitrogenthatthecorndrainedoutofthesoil,bolsteringfertility.Andthepumpkinswereavauablesourceoffoodinthepioneerenvironment.Afterafewseasons,however,thesettlersslowlybegantheprocessoftransformingNewEnglandintoanimageoftheOldWorld,ntingEuropeangrainssuchaswheatandryealongsidethemaize,acroptheyneverabandoned,inpartbecauseitprovedamorereliablesourceoffood.NewEngland,unliketheSouth,didnotcenteritseconomyonanexportcropliketobacco.Norwereitssoilsasfertileasthoseinthemid-Atlanticarea(southofNewEngland),whichbytheeighteenthcenturywasthegreatgrain-producingregionofthecolonies.Instead,NewEngland'ssoilhadamoisturecontentthatmadeitespeciallysuitedforgrowinggrass.Grassyedthepivotalroleintheregion'sfarmecology:thegrassfedcattlethat,itun,producedmanurethatwasspreadoverthefieldsasfertilizerforgrowingcornandothercrops.Grassandcattlethushelpedtomaintainsoilfertility-thekeytoreproducingasustainableformoffarmlife-byrecyclingnutrientsbackintotheThewordtherebyinthepassageisclosestinmeaningAccordingtoparagraph1,EuropeansettlerswereinterestedinareasthathadalreadybeenclearedbyNativeAmericansbecausetheybelievedthatthemostfertilesoilwastobefoundinthosetheywantedtolocatetheirfieldswheretheywoulddoaslittledamagetotheasittooksometimebeforeanewlycearedareabecamesuitableforntingThewordsuitableinthepassageisclosestinmeaningtheywantedtocreatelandscapesthatweremorelikethoseoftheyneededtoreplenishtheirsupplyoftheyhaduseduptheavailableclearedsplittingthetreeinhalfremovingallthebranchesfromakeesapfromreachingthetree'sleavesandThewordgenerallyinthepassageisclosestinmeaningWhichofthesentencesbelowbestexpressestheessentialinformationinthehighlightedsentenceinthepassageIncorrectchoiceschangethemeaninginimportantwaysorleaveoutessentialinformation.Potashfromwoodashwasusedinmanufacturingmanyindustrialproducts,anditwasalsousedtorestorenutrientsthathadbeenlostfromfarmsoil.Theuseofpotashinthemanufactureofawiderangeofindustrialproductsmeantthatfarmerscouldmakeagoodprofitbyexportingtheashesfromthewoodtheyburned.Potashhadmanyindustrialuses,butwhenwoodashesweresoldforpotash,farmssufferedfromthelossofthenutrientsthattheasheswouldhaverestoredtothesoil.Accordingtoparagraph3,oneadvantageofcuttingdowntreesratherthangirdlingthemwasthatcuttingdowntreesreducedtheriskofaddedalkalinesubstancestothepnutrientsintheThewordtendinginthepassageisclosestinmeaningtakingcareWhydoestheauthordiscussthesettlers'needtoproducefood TosupporttheideathatthesettlerscutdowntreestoclearthelandonlybecausetheyhadnootherTheyntedmorecornthanothercropsbecauseitdthesoilwiththewidespreadpracticeofkeecattleinthetheregularrecyclingofnutrientsbackintothetheamountofwaterinthethefertilityoftheParagraph4:Withtheirveryexistencedependentonthsuccessfulproductionoffood,farmershadlittle,ifany,timeforremovingstumpsandstones.■Instead,theyadaptedtothehalf-clearedfieldsbyntingcorn(maize)andgrass;bothgrewwellinsuchanenvironment.■Apatternofextensivefarmingbegantoemerge.■Ratherthancarefullytendingarableland,engagingincroprotation,manuring,andremovingallstumpsandstones,allrecognizedaspartofproperagriculturalpracticeinEurope,NewEnglandfarmerssimplyexploitedthesoilandthenforgedaheadwiththeclearingofnewland.■Cuttingdowntreesremainedhardwork,butitwaseasiertopartiallycleartheland,ntit,andthenmoveontoanothersmallplotthantoconstantlyimprovethesoilononefieldtothehighOldWorld(European)standards.Thesettlersweretoobusyfiguringouthowtoproducefoodrapidlytoworryaboutefficientagriculturalpractices.LookatthefoursquaresthatindicatewherethefollowingsentencecouldbeaddedtotheWherewouldthesentencebestfit?ClickonasquaretoaddthesentencetotheDragyourchoicestothespaceswheretheybelong.Toreviewthepassage,clickonViewOncethesupplyofsuitableclearedlandranout,thesettlershadtoclearnewlandbeforetheycouldnt,generallyconvertingthetreestheyremovedintolumber,fuel,orpotash.Thesettlers'attempttofollowwhat,inEurope,wasconsideredproperfarmingpracticeswassoonabandonedastheydiscoveredthatfoodcouldbegrownmoreefficientlyinotherways.Becauseclearingfieldstooktimeandtheneedforfoodwaspressing,farmersweredtoresorttoextensivefarmingpracticesratherthanfollowtheiroldEuropeanfarmingsystem.Afterntingcorn(maize)enoughtimestodraintheexcessnitrogenoutofthesoil,thesettlerswereabletogrowmorefamiliarEuropeancropssuchaswheatandrye.ThesettlersdevelopedafarmecologythateventuallymadetheregionmoreproductivethantheSouthoreventhemid-Atlanticarea.Thesoilwasnotparticularlyfertile,butgrassgrewwellandfedcattlethatproducedmanure,whichinturnservedasfertilizerforcropsandrecyclednutrientsbackintothesoil.【P4】TheClimateofAtthemostgenerallevel,twomajorclimaticsdetermineJapan’sweather.PrevailingwesterlywindsmoveacrossEurasia,sweepovertheJapaneseislands,andcontinueeastwardacrossthePacificOcean.Inaddition,greatcyclonicairflows(massesofrapidlycirculatingair)thatariseoverthewesternequatorialPacificmoveinawheel-likefashionnortheastwardacrossJapanandnearbyregions.DuringwintermonthsheavymassesofcoldairfromSiberiadominatetheweatheraroundJapanPersistentcoldwindsskimacrosstheSeaofJapanfromthenorthwest,pickingupmoisturethattheydepositasseveralfeetofsnowonthewesternsideofthemountainrangesonHonshuIsland.Asthecoldairdropsitsmoisture,itflowsoverhighridgesanddowneasternslopestobringcold,relativelydryweathertovalleysandcoastalinsandcities.InspringtheSiberianairmasswarmsandlosesdensity,enablingatmospherecurrentsoverthePacifictosteerwarmerairintonortheastAsia.Thiswarm,moisture-ladenaircoversmostofsouthernJapanduringJuneandJuly.Theresultinglatespringrainsthengivewaytoadriersummerthatissufficientlyhotandmuggydespitetheislandchain’snortherlylatitude,toallowwidespreadricecultivation.Summerheatisfollowedbythehighlyunpredictableautumnrainsthat panytheviolenttropicalwindstormknownastyphoons.ThesecyclonicstormsoriginateoverthewesternPacificandtravelingreatclockwisearcs,initiallyheadingwesttowardthePhilippinesandsouthern,curvingnorthwardlaterintheseason.ColdweatherdrivesthesestormseastwardacrossJapanthroughearlyautumnrevitalizingSiberianairmassandusheringinanewannualweathercycle.ThisyearlycyclehasyedakeyroleinshaJapanesecivilization.Ithasassuredtheislandsampleprecipitation,rangingirregularlyfrommorethan200centim