四级英语阅读理解模拟题及答案.docx

四级英语阅读理解模拟题及答案Treesshouldonlybeprunedwhenthereisagoodandclearreasonfordoingsoand,fortunately,thenumberofsuchreasonsissmall.Pruninginvolvesthecuttingawayofobergrownandunwantedbranches,andtheinexperiencedgardenercanbeencouragedbythethoughtthatmoredamageresultsfromdoingitunnecessarilythanfromleavingthetreetogrowinitsownway.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.Whatwastheautho