Passagestructure(篇章结构)下面是一篇杂志文章，请将标有A－F的段落插入文章中标号为1－5的合适位置，使这篇文章意义完整，结构连贯；其中有一个段落是多余的。Everyyea

　　Passagestructure(篇章结构)

　　下面是一篇杂志文章，请将标有A－F的段落插入文章中标号为1－5的合适位置，使这篇文章意义完整，结构连贯；其中有一个段落是多余的。

　　Everyyearmoreandmoreplantsandanimalsdisappearnevertobeseenagain．

　　1．________

　　Everydaythousandsofspecies(种类)ofanimalsdrawclosertoextinction(灭绝)．Therearecountlessnumbersofspecieswhichmaybecomeextinctbeforetheyareevendiscovered．

　　2．________

　　Theproblemisacid(酸)rain．Acidrainisakindofairpollution．

　　3．________

　　Theraininmanyplacesisn’tnaturalandcleananymore．It’sfullofacidchemicals．

　　4．________

　　Butdeadfishmaybejustthebeginningoftheproblem．Scientistsarefindingothereffectsofacidrain．

　　5．________

　　Nowscientistsarealsobeginningtostudytheeffectsofacidrainonlargeranimals．ForexampletheybelievethatsomedeerinPolandarelesshealthybecauseofacidrain．Ifdeerarehurtbytherainwhataboutpeople?Thisisthequestionmanypeoplearebeginningtoask．Nooneknowstheansweryet．Butitisanimportantquestionforusall．

　　A．Seldomdoesitrainandthereislittlefreshwaterhereforthefish．Aseriesofdevelopmentprojectshasdestroyedthenaturalenvironment．Wasteofdifferentkindscanbeseenhereandthere．Thishascausedaseriousproblemforfishandotheranimalslivingaround．

　　B．Insomelargeareastreesaredying．Notjustonetreehereandtherebutthewholeforests．Atfirstscientistscouldn’tunderstandwhy．Therewerenobugs(虫)ordiseasesinthesetrees．Theweatherwasnotdry．Butnowtheythinkthattherainwasthecause．Acidrainismakingtheearthmoreacidicintheseareas．Somekindsoftreescannotliveinthesoilthatisveryacidic．

　　C．Whenitfallsinlakesitchangesthemtoo．Thelakesbecomemoreacidic．Acidwaterislikevinegar(醋)orlemonjuice．Ithurtswhenitgetsinyoureyes．Italsokillstheplantsandanimalsthatusuallyliveinlakewater．Thatiswhythefisharedyinginlakes．

　　D．Itiscausedbyfactoriesthatburncoaloroilorgas．Thesefactoriessendsmokeintotheair．Thewindoftencarriesthesmokefarfromthefactories．Someoftheharmfulsubstances(物质)inthesmokemaycomedownwiththerainhundredsofmilesaway．

　　E．Strangely