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1温馨提示：此套题为Word版，请按住Ctrl,滑动鼠标滚轴，调节合适的观看比例，答案解析附后。关闭Word文档返回原板块。课堂10分钟达标Asandstorm,alsoknownasaduststorm,isexactlywhatitsoundslike.Averystrongwindstormespeciallyinthedesertcarriescloudsofsandordustthatgreatlyreducesvisibility.Thiswindisusuallycausedbyconvectioncurrents(对流气流),whicharecreatedbyintenseheatingoftheground,andisusuallystrongenoughtomoveentiresanddunes.Airisunstablewhenheated,andthisinstabilityintheairwillcausehigherwindstomixwithwindsintheloweratmosphere,producingstrongsurfacewinds.Sandstormscandisturbpeople’stravel,andcansometimesdestroywholeroads,anddryflatareas.SimilarduststormscanbefoundontheplanetMars,andarethoughttobeseasonal.Today,thedestructionofforestsandtoomuchfarmingoffarmlandcanleadtosandstorms.Toomuchuseofwaterresourcescanalsocausesandstorms.IntheUnitedStatesofAmerica,sandstormsarerarebecauseofthelackoflargedesertsandmoreimportantlythedevelopmentofproperagriculturaltechniques.ThelastrecordeddestructivesandstorminAmericanhistorywastheDustBowl,whichoccurredonJuly16,1971and2waswidelyrecordedbymeteorologists(气象学家).Toprotectthemselvesfromsandstorms,somepeoplewearprotectivesuits.Specialequipmentcanbefixedinsomecarstopreventsandfromgettingintotheengine.Sandstormscancausecoughs,andthesandanddusthasalsobeenknowntocarry“infectiousdiseases”.Sandparticles,unlikedustones,willblockairpassages,andcauseapersonwhobreathesthemintochoke.Dustparticlesmaycauseanallergic(过敏的)reaction.Ⅰ.Skimthepassageandfindthemainideaquickly.____________________________________________________________答案：Thepassageaimstotellustheformationanddamageofsandstorms.Ⅱ.Readthepassageagainandchoosethebestanswers.1.Whichofthefollowingplaysthefirstpartinformingsandstorms?A.Theinstabilityofthesand.B.Theinstabilityofthewind.C.Theintenseheatingoftheground.D.Thespeedofthewind.【解析】选C。细节理解题。从第一段的句子“Thiswindisusuallycausedbyconvectioncurrents,whicharecreatedbyintenseheatingoftheground”可知沙尘暴的最初形成是因为地面的热量。32.Fromthesecondparagraph,wecanlearnthatatpresent .A.sandstormsaremoreoftenseenonMarsthanonEarthB.sandstormshaveledtothelackofcleanwaterresourcesC.farmingbringsmoreharmthanbenefitstohumansD.humanactivitiesareamajorcauseofsandstorms【解析】选D。细节理解题。从第二段的句子“Today,thedestructionofforestsandtoomuchfarmingoffarmlandcanleadtosandstorms.Toomuchuseofwaterresourcescanalsocausesandstorms.”可知现在沙尘暴的形成主要是因为人的活动。3.Theauthorwillmostprobablyagreethat________.A.therewillsoonbenosandstormsintheUSAB.humanshaven’tthoughtofanywaytodealwithsandstormsC.deathcausedbysandstormsisincreasingallthetimeD.humansshouldmakemoreeffortstostopsoilturningintodesert【解析】选D。推理判断题。从第三段的句子“IntheUnitedStatesofAmerica,sandstormsarerarebecauseofthelackoflargedesertsandmoreimportantlythedevelopmentofproperagriculturaltechniques.”可知作者认为人类应该努力不让土地变成沙漠。关闭Word文档返回原板块