【MeiWei81-优质实用版文档】大学英语四级阅读理解试题及答案（四）十六Treesshouldonlybeprunedwhenthereisagoodandclearreasonfordoingsoand,fortunately,thenumberofsuchreasonsissmall.Pruninginvolvesthecuttingawayofobergrownandunwantedbranches,andtheineGperiencedgardenercanbeencouragedbythethoughtthatmoredamageresultsfromdoingitunnecessarilythanfromleavingthetreetogrowinitsownway.First,pruningmaybedonetomakesurethattreeshaveadesiredshapeorsize.Theobjectmaybetogetatreeoftherightheight,andatthesametimetohelpthegrowthofsmallsidebrancheswhichwillthickenitsappearanceorgiveitaspecialshape.Secondly,pruningmaybedonetomakethetreehealthier.Youmaycutdiseaedordeadwood,orbranchesthatarerubbingagainsteachotherandthuscausewounds.Thehealthofatreemaybeencouragedbyremovingbranchesthatareblockingupthecentreandsopreventingthefreemovementofair.Oneresultofpruningisthatanopenwoundisleftonthetreeandthisprovidesaneasyentryfordisease,butitisawoundthatwillheal.Oftenthereisaracebetweenthehealingandthedeseaseastowhetherthetreewillliveordie,sothatthereisaperiodwhenthetreeisatrisk.Itshouldbetheaimofeverygardenertoreducewhichhasbeenprunedsmoothandclean,forhealingwillbesloweddownbyroughness.Youshouldallowthecutsurfacetodryforafewhursandthenpaintitwithoneofthesubstancesavailablefromgardenshopsproducedespeciallyforthispurpose.Pruningisusuallywithoutinterferencefromtheleavesandalsoitisveryunlikelythatthecutsyumakewillbleed.Ifthisdoeshappen,itis,ofcourse,impossibletopaintthemproperly.1.Pruningshouldbedoneto_.a.makethetreegrowtallerb.improvetheshapeofthetreec.getridofthesmallbranchesd.makethesmallbranchesthicker2.Treesbecomeunhealthyifthegardener_.a.allowstoomanybranchestogrowinthemiddleb.doesnotprotectthemfromwindc.forcesthemtogrowtooquicklyd.damagessomeofthesmallsidebranches3.Whyisaspecialsubstancepaintedonthetree?a.Tomakeawoundsmoothb.Topreventdiseaseenteringawoundc.Tocoveraroughsurfaced.Tohelpawoundtodry4.Agoodgardenerprunesatree_.a.atintervalsthroughouttheyearb.asquicklyaspossiblec.occasionallywhennecessaryd.regulareverywinter5.Whatwastheauthorspurposewhenwritingthispassage?a.Togivepraticalinstructionforpruningatree.b.Togiveageneraldescriptionofpruningc.ToeGplainhowtreesdevelopdiseasesd.Todiscussdifferentmethodsofpruning.答案：babca十七OnThursdayafternoonMrs.Carke,dressedforgoingout,tookherhandbagwithhermoneyandherkeyinit,pulledthedoorbehindhertolockitandwenttotheover60sClub.ShealwayswentthereonThursdays.Itwasaniceoutingforanoldwomanwholivedalone.AtsiGoclockshecanehome,letherselfinandatoncesmeltcigarettesmoke.Cigarettesmokeinherhouse?How?How?Hadsomeonegotin?Shecheckedthebackdoorandthewindows.Allwerelockedorfastened,asusual.Therewasnosignofforcedentry.Overacupofteashewonderedwhethersomeonemighthaveakeythatfittedherfrontdoor-amasterkeyperhaps.SoshestayedathomethefollowingThursday.Nothinghappened.Wasanyonewatchinghermovements?OntheThursdayafterthatshewentoutatherusualtime,dressedasusual,butshedidntgototheclub.Insteadshetookashortcuthomeagain,lettingherselfinthroughhergardenandthebackdoor.Shesettleddowntowait.Itwasjustafterfouroclockwhenthefrontdoorbellrang.Mrs.Clarkewasmakingacupofteaatthetime.Thebellrangagain,andthensheheardherletter-boGbeingpushedopen.Withthekettleofboilingwaterinherhand,shemovedquietlytowardsthefrontdoor.Alongpieceofwireappearedthroughtheletter-boG,andthenahand.Thewireturnedandcaughtaroundtheknobonthedoor-lock.Mrs.Clarkeraisedthekettleandpouredthewateroverthehand.Therewasashoutoutside,andtheskinseemedtodropoffthefingerslikeaglove.Thewirefelltothefloor,thehandwaspulledback,andMrs.Clarkeheardthesoundofrunningfeet.1.Mrs.ClarkeloodedforwardtoThursdaybecause_.a.sheworkedataclubonthedayb.shesaidvisitorsonThursdaysc.shevisitedaclubonThursdayd.aspecialvisitorcameonThursday2.Ifsomeonehadmadeaforcedentery,_.a.Mrs.Clarkewouldhavefoundabrokendoororwindowb.heorshewasstillinthehousec.thingswouldhavebeenthownaboutd.heorshewouldhaveneededamasterkey3.OnthethirdThursdayMrs.Clarkewentout_.a.becauseshedidntwanttomisstheclubagainb.toseeifthethiefwashngingaboutoutsidec.totheclubbutthenchangedhermindd.inanattempttotrickthethief4.Thelockonthefrontdoorwasonewhich_.a.neededapieceofwiretoopenitb.couldheopenedfrominsidewithoutakeyc.couldtbeopenedwithoutakeyd.usedaknobinsteadofakey5.Thewirefeeltothefloor_.a.becauseMrs.Clarkerefusedtoopenthedoorb.whenthemansglovedroppedoffc.becauseitwastoohottoholdd.becausethemanjustwantedtogetaway答案：cadbd十八Manypeoplebelievetheglarefromsnowcausessnowblindnenss.Yet,darkglassesornot,theyfindthemselvessufferingfromheadachesandwateringeyes,andevensnowblindness,wheneGposedtoseveralhoursofsnowlight.TheUnitedStatesArmyhasnowdeterminedthatglarefromsnowdoesnotcausesnowblindnessintroopsinasnow-coveredcountry.Rather,amanseyesfrequentlyfindnothingtofoucsoninabroadeGpan