Unit4Exploringplants植物是我们生活中必不可少的一个部分，那么你知道植物的重要性吗？Plantsformthebasicfoodstapleforalllifeforms.Theyarethemajorsourceoffoodandoxygenonearth，sincenoanimalcansupplythesenecessarycomponentswithoutplants.Therearemanydifferenttypesofcashcropsthatproducemoneyforfarmers.Oliveoilcomesfromolives，cornoilcomesfromcorn，andpeanutoilcomesfrompeanuts.Typicalagriculturalproductslikecorn，wheat，rye，andriceareallconsideredcashcrops.Coffeeplantsproducebeansthatareusedtomakecoffee；cocaplantsgiveuschocolate；vanillaplantsgrowlongthinbeansthatareusedtoproducevanillaflavoring.Plantsarealsousedinagriculturetohelpreducewindspeed.Plantingtreesinarowpreventsthewindfromblowingawaythevaluabletopsoil.Intheforest，treesactasshelterformanyorganisms.Plantsarealsoimportantfortheoverallecologyofanarea.Rootshelptostabilizesoilandpreventthesoilerosionbywaterrunoff.Plantsarealsoimportantinouratmospherebecausetheyusecarbondioxideandgiveoffoxygenwhiletheyundergophotosynthesis.Plantsarealsousedintheurbansettingtoreducenoise，produceshade，andtobeautifyanarea.Treesaddvaluetohomesandcommunities.Plantsareessentialtothebalanceofnatureandinpeople'slives.Greenplants，i.e.，thosepossessingchlorophyll(叶绿素)，producetheirownfoodandgiveoffoxygenintheprocesscalledphotosynthesis(光合作用)，inwhichwaterandcarbondioxidearecombinedbytheenergyoflight.Plantsaretheultimatesourceoffoodandmetabolicenergyfornearlyallanimals，whichcannotproducetheirownfood.Besidesfoods，plantproductsvitaltohumansincludewoodandwoodproducts，fibers，drugs，oils，latex，pigments，andresins.Coalandpetroleum(石油)arefossilsubstancesofplantorigin.Thusplantsprovidepeoplenotonlysustenancebutshelter，clothing，medicines，fuels，andtherawmaterialsfromwhichinnumerableotherproductsaremade.两个诱思问题1．Whatisthepurposeofthesecondparagraph?2．Whyareplantsimportanttoouratmosphere?【答案】1.Givesomeexamplesabouttheuseofplants.2.Becausetheyusecarbondioxideandgiveoffoxygenwhiletheyundergophotosynthesis.SectionⅠReading(WarmingUp,Prereading，Reading&Comprehending)Ⅰ.根据词性及英文释义写出单词的正确形式1．adj.farawayinspaceortime2．n．balanceforweighing；oneofthetwopansonabalance；relativesize，extent，scope，etc.3．n．struggle；fight；disagreement4．n．effort；attempttodosth.newordifficult5．adj.fixed，fastenedordrawntogetherfirmly6．n．actofputtingalimitonsb./sth.7．n．qualityofspeaking，writinginaneasysmoothmanner8．vi.tobeattractiveorinteresting(tosb.)【答案】1.distant2.scale3.conflict4.endeavour5.tight6.restriction7.fluency8.appealⅡ.短语填空datebackto；onalargescale；comeacross；quantitiesof；failto；takeinterestin；resultin；appealto1．Theyarepreparingforwar．2．Stressandtirednessoftenalackofconcentration.3．DoestheideaofworkingforIBMyou?4．ThiscastleRomantimes.5．Smallpoisonweredetectedinthedeadman'sstomach.【答案】1.onalargescale2.resultin3.appealto4.datesbackto5.quantitiesofⅠ.阅读P32－33课文内容，从三个选项中选择最佳答案1．Thefirstrecordedplantexplorationhappened.A．inthe18thcenturyB．about1，500yearsagoC．about1500BC2．Whoisnotacollectormentionedinthepassage?A．Fatherd'Incarville.B．TheQueenofEngland.C．RobertFortune.3．PlantscollectorsmetmanydifficultiesEXCEPT．A．lackofmoneyB．theconflictswithlocalpeopleC．restrictionsonthemovementofEuropeans4．WhichofthefollowingstatementsisTRUEaccordingtothetext?A．Thefirstplantc...
