英语四级阅读理解考试题及答案.pdf

英语四级阅读理解考试题及答案

英语四级阅读理解考试题及答案

英语四级阅读理解考试题及答案篇1

Treesshouldonlybeprunedwhenthereisagood

andclearreasonfordoingsoand,fortunately,the

numberofsuchreasonsissmall.Pruninginvolvesthe

cuttingawayofobergrownandunwantedbranches,and

theinexperiencedgardenercanbeencouragedbythe

thoughtthatmoredamageresultsfromdoingit

unnecessarilythanfromleavingthetreetogrowin

itsownway.

First,pruningmaybedonetomakesurethattrees

haveadesiredshapeorsize.Theobjectmaybetoget

atreeoftherightheight,andatthesametimeto

helpthegrowthofsmallsidebrancheswhichwill

thickenitsappearanceorgiveitaspecialshape.

Secondly,pruningmaybedonetomakethetree

healthier.Youmaycutdiseaedordeadwood,or

branchesthatarerubbingagainsteachotherandthus

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causewounds.Thehealthofatreemaybeencouraged

byremovingbranchesthatareblockingupthecentre

andsopreventingthefreemovementofair.

Oneresultofpruningisthatanopenwoundis

leftonthetreeandthisprovidesaneasyentryfor

disease,butitisawoundthatwillheal.Oftenthere

isaracebetweenthehealingandthedeseaseasto

whetherthetreewillliveordie,sothatthereisa

periodwhenthetreeisatrisk.Itshouldbetheaim

ofeverygardenertoreducewhichhasbeenpruned

smoothandclean,forhealingwillbesloweddownby

roughness.Youshouldallowthecutsurfacetodryfor

afewhursandthenpaintitwithoneofthe

substancesavailablefromgardenshopsproduced

especiallyforthispurpose.Pruningisusually

withoutinterferencefromtheleavesandalsoitis

veryunlikelythatthecutsyumakewillbleed.If

thisdoeshappen,itis,ofcourse,impossibletopaint

themproperly.

1.．Whyshouldpruningbedone?

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A