小学、初中、高中各种试卷真题知识归纳文案合同PPT等免费下载www.doc985.com课时作业(八)Unit3SectionⅡGrammarandusage&IntegratedskillsⅠ.阅读理解APeoplewhoaregoodatgrowingplantsknowthatit'spossibletoplantwhatseemstobealifelessstickandproduceatreeorotherkindsofplants.Thestickisreallywhatiscalledahardwoodcutting.Fromthesecuttings,trees,vines(藤蔓)exceptpinetreescangrow.Theyarecalledhardwoodbecausethepiecesarewoodyratherthanleafy.Gardenerscanexpectcloseto100percentsuccesswithplantssuchasgrape,gooseberry,privet,spiraeaandhoneysuckle.However,thismethoddoesnotworkwithapple,mapleoroaktrees,forexample.Becausetheylackleaves,hardwoodcuttingsarelessperishable(易腐烂的)thansoftwoodcuttings.Ifyouwanttodevelopagreenthumb—orgetreallygoodatgrowingplants—startyoureffortwithhardwoodcuttingsofwillow.Willowtreesoftenspreadfrombranchesthattakerootontopofthegroundthroughthewinter.Mostotherplantsdemandalittlemoreattention.Autumnisagoodtimetostarthardwoodcuttings.First,choosesomeshoots(新枝)thatgrewduringthemostrecentgrowingseason—theyoungestshoots.Cuttheshootstoalengthofabout15centimeters.Makesureyourememberwhichendwasup—theendthatisfartherfromtheroot.Expertsdothisbycuttingthebottomsoffdirectlyandthetopsatananglesotheyavoidmistakesduringplanting.Then,placethebottomofeachcuttingintosomewell-drained(排水良好的)soil.Ifyouhavetoplantinthespring,thecuttingsneedtobekeptcoolandwetthroughthewinter.Thetraditionalmethodistoplacethecuttingstogetherandburythemupsidedowninthesoil.Thisletsthebottomsofthecuttingsbefirsttofeelthewarmingeffectsofspringsunontheground.Putthecuttingsinaclosedplasticbag,putawetpapertowelaroundthebag,andthenputthewholethinginanotherplasticbag.1.Whatcanwelearnaboutwoodyplantsaccordingtothetext?A.Gardenerscanget100%successwiththem.B.Thecuttingsfromthemdryoutbeforerootsform.C.Allwon'tgrowfromhardwoodcuttings.D.They'refarlessreliablethanleafyplants.2.Whichofthefollowingfitsthemethodofhardwoodcuttingsproperly?A.Appletrees.B.Oaktrees.C.Pinetrees.D.Willowtrees.3.Whatisthefourthparagraphmainlyabout?A.Howtomakecuttings.B.Whentomakecuttings.C.Wheretoputcuttings.D.Whattomindatchoosing.4.Whatdoestheauthorstressaboutcuttingsinthelastparagraph?A.Thechoice.B.Thestorage.小学、初中、高中各种试卷真题知识归纳文案合同PPT等免费下载www.doc985.com小学、初中、高中各种试卷真题知识归纳文案合同PPT等免费下载www.doc985.comC.Thetemperature.D.Theseasons.BToday,Chinahasconducteditsfirst3Dprintingexperimentinspaceinanewlylaunchedspacecraft,whichwasputintolow-EarthorbitbyChina'sLongMarch5Bheavyliftcarrierrocket.VideobroadcastonCCTVshowedthattheprinterhasprintedaflatsectionofahoneycomb-shaped(蜂巢状的)structureaswellasasymbolofChinaAerospaceScienceandTechnologyCorp,theparentcompanyoftheChinaAcademyofSpaceTechnology.Theexperimentwasdonebya3Dprinter,developedandbuiltbyitsBeijingSpacecraftsManufacturingFactoryinsidetheprototypeofChina'snew-generationmannedspacecraft.Theprinter,namedtheSpace-BasedCompositeMaterial3DPrintingSystem,usescarbonfiber-reinforcedmaterialstoautonomouslyprintobjects.Itisinstalledinthereentrymoduleoftheexperimentalspaceship,andwillbebroughtbacktoEarthoncethemodulereturns.Theprinterfeaturesadvancedtechnologiesinmaterialmodeling,precisioncontrolandautomation.Oncethespace-based3Dprintingtechnologybecomesoperationallyready,itcanextensivelybenefitspaceprogramsasastronautscan...