PAGEPAGE1ParagraphTheword“presumably”inthepassageisclosestinmeaningAccordingtoparagraph1,allofthefollowingaretrueofancestralplantsEXCEPTTheyhadcellulose-basedcellTheywerecloselyrelatedtogreenTheywereabletostoreParagraphThephrase“subjectedto”inthepassageisclosestinrestricteddistantexposed

TheEvolutionaryOriginofPlantsTheevolutionaryhistoryofplantshasbeenmarkedbyaseriesofadaptations. photosyntheticsingle-celledorganismsthatgaverisetoplantspresumablylackedtrueroots,stems,leaves,andcomplexreproductivestructuressuchasflowers.Allofthesefeaturesappearedlaterintheevolutionaryhistoryofplants.Oftoday’sdifferentgroupsofalgae,greenalgaeareprobablythemostsimilartoancestralplants.Thissuppositionstemsfromthe evolutionary)relationshipbetweenthetwogroups.DNAcomparisonshaveshownthatgreenalgaeareplants’closestlivingrelatives.Inaddition,otherlinesofevidencesupportthehypothesisthatlandplantsevolvedfromancestralgreenalgaeusedthesametypeofchlorophyllandaccessorypigmentsinphotosynthesisasdolandplants.Thiswouldnotbetrueofredandbrownalgae.Greenalgaestorefoodasstarch,asdolandplantsandhavecellwallsmadeofcellulose,similarincompositiontothoseoflandplants.Again,thegoodstorageandcellwallmoleculesofredandbrownalgaearedifferent.Todaygreenalgaelivemainlyinfreshwater,suggestingthattheirearlyevolutionaryhistorymayhaveoccurredinfreshwaterhabitats.Ifso,thegreenalgaewouldhavebeensubjectedto

[TC1presumeB批注[TC2]:這道題可以直接做取非處理，Theancestorsofplantswere[TC3]subjectedto:遭受；承受；使某人經(jīng)歷某事。exposedtocombinedParagraph

environmentalpressuresthatresultedinadaptationsthatenhancedtheirpotentialtogiverisetoland-dwellingorWhatcanbeinferredfromparagraph ?Theenvironmentalconditions

批注[TC4]:推斷題。AaboutancientgreenTheylivedinagenerallywetTheyadaptedbettertochangesinwatertheenvironment.theocean.TheyhadlivedprimarilyonParagraphTheword“desolate”inthepassageisclosestinmeaningtodriedWhichofthesentencesbelowbestexpressestheessentialinformationinthehighlightedsentenceinthepassage?IncorrectchoiceschangethemeaninginimportantwaysorleaveoutessentialTerrestrialplantshadtheadvantagesofnothavingrivalsandhavingeasyaccesstophotosyntheticmaterialTheabundanceofphotosyntheticpioneeringplantsOnceplantshadeliminatedtheirevolutionaryprocessproceeded

freshwaterhabitats,unlikethoseofoceanhabitats,arehighlyvariable.█Watertemperaturecanfluctuateseasonallyorevendailyandchanginglevelofrainfallcanleadtofluctuationsintheconcentrationofchemicalinthewateroreventoperiodinwhichtheaquatichabitatdriesup.█Ancientfreshwatergreenalgaemusthaveevolvedfeaturesthatenablethemtoperiodsofdryness.█Theseadaptationsservedtheirdescendantwellastheyinvadedland.Theterrestrialworldisgreennow,butitdidnotstartoutthatway.Whenplantsfirstmadethetransitionashoremorethan400millionyearsago,thelandwasbarrenanddesolate,inhospitabletolife.Fromaplant’sevolutionaryviewpoint,however,itwasalsoalandofopportunity,freeofcompetitorsandpredatorsandfullofcarbondioxideandsunlight(therawmaterialsforphotosynthesis,whicharepresentinfarhigherconcentrationsinairthaninwater).Sooncenaturalselectionhadshapedtheadaptationsthathelpedplantsovercometheobstaclestoterrestrialliving,plantsprosperedanddiversified.

B他們出現(xiàn)比較，不選。C他們應該在freshwater而不是oceanD選項說在freshwaterhabitat，錯。批注[TC5]:Desolate找個跟barren貧瘠的意思最為接近的詞，C最合適[TC6]:原句包含兩層概念1有很多機會，沒有競爭，2CO2和位。選A。Plantevolutioneliminatedcompetitorsmoreefficient.Accordingtoparagraph4,whichofthefollowingistrueabouttheterrestrialworldatthetimeitwascolonizedbyplants?ithaddeveloped400millionyearsitlackedthepresenceofany

[TC7]:定位原文thelandwasbarrenanddesolate,inhospitableto的。選D，缺少生物的存在。Paragraphtheword“posed”inthepassageisclosestinmeaningtoAccordingtoparagraph5,allofthefollowingareproblemsthatearlyterrestrialplantshadtoovercomeExcepttheabsenceofastructuretosupportthebodyoftheplantmineralsthroughtheplantWhatpurposedoesparagraph5serveinthelargerdiscussionoftheoriginsofterrestrialplants? ToemphasizehowlongittookforplantsadaptedeasilytotheirnewterrestrialenvironmentToexplainhowplantcolonizationterrestrialworldTodescribehowancestralplants

Whenplantspioneeredtheland,theyfacedarangeofchallengesposedbyterrestrialenvironments.Onland,thesupportivebuoyancyofwaterismissing,theplantisnolongerbathedinanutrientsolution,andairtendstodrythingsout.Theseconditionsfavoredtheevolutionofthestructuresthatwaterandnutrientstoallpartsofplant,andstructuresthatconservewater.Theresultingadaptationstodrylandincludesomestructuralfeaturesthataroseearlyinplantevolution;nowthesefeaturesarecommontovirtuallyalllandplant.Theyincluderootsorrootlikestructures,awaxycuticlethatcoversthesurfacesofleavesandstemsporescalledstomatainleavesandstemsthatallowgasexchangebutclosewhenwaterisscarce,thusreducingwaterloss.Otheradaptationsoccurredlaterinthetransitiontoterrestriallifeandnowwidespreadbutnotuniversalamongplants.Theseincludeconductingvesselsthattransportwaterandmineralsupwardfromtherootsandthatmovethephotosyntheticproductsfromtheleavestotherestof

as:PRESENT。選B[TC9]5段首先提出將面對各種挑戰(zhàn)，下面一一列舉。A對應……airtendstodrythingsout.Theseconditionsfavoredtheevolutionofthestructuresthatsupportthebody,vesselsthattransportwaterandnutrientstoallpartsofplant,andstructuresthatconservewater.說了這些情況導致輸水和營養(yǎng)（D項。批注[TC10植物到土地上，會面臨各種挑戰(zhàn)，后面解釋了他們身體構(gòu)造如何變化使得適合生存在陸地。D合理。

theplantbodyandthestiffeningsubstancelignin,whichsupporttheplantbody,helpingitexposemaximumsurfaceareatosunlight.Paragraphmadebyterrestrialplantshadwhichofthefollowingeffect?’usableinbothlandandwaterenvironmentsdiminishedonlandspeciesamongplantsWhichofthefollowingbestdescribestheauthor’spresentationoftheinformationaboutlandplantsevolutionaryrelationshipsbetweenspecificspeciesofalgaeandlandplantsplantsunderwentintheprocessoftheauthorestablishesapatternofpantgroupsTheauthorresentsevidencetosupportthehypothesisthatplantsfirstfullytoland

Theseadaptationsallowedanincreasingdiversityofplantformstoexploitdryland.Lifeonland,however,alsorequirednewmethodsoftransportingspermtoeggs.Unlikeaquaticandmarineforms,landplantscannotalwaysrelyonwatercurrentstocarrytheirsexcellsanddispersetheirfertilizedeggs.Sothemostsuccessfulgroupsoflandplantsarethosethatevolvedmethodsoffertilizedsexcelldispersalthatareindependentofwaterandstructuresthatprotestdevelopingembryosfromdryingout.Protectedembryosandwaterlessdispersalofsexcellswereachievedwiththeoriginofseedplansandthekeyevolutionaryinnovationsthattheyintroduced:pollen,seeds,andlater,flowersand

批注[TC11]:適應性變化導致繁殖B,沒說陸地上多樣性減少C原文沒onland,however,alsorequirednewmethodsoftransportingspermtolandplantscannotalwaysrelyonwatercurrentstocarrytheirsexcellsanddispersetheirfertilizedeggs.從而選擇B答案Lookatthefoursquares[█] ?Theenvironmentalconditions

indicatewherethefollowingsentencecouldbeaddedtothepassage.Scientistsbelievethatchemicalchangesandathickerexterior,amongotherthings,mayhavehelpedancientalgaeovercomethe

freshwaterhabitats,unlikethoseofoceanhabitats,arehighlyvariable.█Watertemperaturecanfluctuateseasonallyorevendailyandchanginglevelofrainfallcanleadtofluctuations

說明。故應該插入最后一個空D。Wherewouldthesentencebestfit?Clickonasquaretoaddthesentencetothepassage.Directions:Anintroductorysentenceforabriefsummaryofthepassageisprovidedbelow.CompletethesummarybyselectingtheTHREEanswerchoicesthatexpressthemostimportantideasinthepassage.Somesentencesdonotbelonginthesummarybecausetheyexpressideasthatarenotpresentedint