开头可以用这几个～根据情况自己选用～

　　1.______________isknownasoneofthemostseriousproblemsin

　　today‘ssociety.Wecanseeitalmosteverywhere.Asthegraphdepicts,

　　______________.

　　Nowadaysalthoughmoreandmorepeople______________,still

　　therearesomewhothink______________,theymaythink______________.

　　Oneofthegreatwritersoncesaidthat______________.Nowit

　　stillhasarealisticsignificance.

　　TheEnglishproverbsays,______________.Thisisquitetrue

　　because______________.

　　Nowadaysmoreandmorepeoplearebeginningtobeawareofthe

　　seriousnessof______________.

　　以下各个方面都有～自己选用

　　1表示原因

　　1)Therearethreereasonsforthis.

　　2)Thereasonsforthisareasfollows.

　　3)Thereasonforthisisobvious.

　　4)Thereasonforthisisnotfartoseek.

　　5)Thereasonforthisisthat...

　　6)Wehavegoodreasontobelievethat...

　　2.表示好处

　　1)Ithasthefollowingadvantages.

　　2)Itdoesusalotofgood.

　　3)Itbenefitsusquitealot.

　　4)Itisbeneficialtous.

　　5)Itisofgreatbenefittous.

　　3.表示坏处

　　1)Ithasmoredisadvantagesthanadvantages.

　　2)Itdoesusmuchharm.

　　3)Itisharmfultous.

　　4.表示重要、必要、困难、方便、可能

　　1)Itisimportant(necessary,difficult,convenient,possible)forsb.todosth.

　　2)Wethinkitnecessarytodosth.

　　3)Itplaysanimportantroleinourlife.

　　5.表示措施

　　1)Weshouldtakesomeeffectivemeasures.

　　2)Weshouldtryourbesttoovercome(conquer)thedifficulties.

　　3)Weshoulddoourutmostindoingsth.

　　4)Weshouldsolvetheproblemsthatweareconfronted(faced)with.

　　6.表示发生变化

　　1)Somechangeshavetakenplaceinthepastfiveyears.

　　2)Agreatchangewillcertainlybeproducedintheworld’scommunications.

　　3)Thecomputerhasbroughtaboutmanychangesineducation.

　　7.表示事实、现状

　　1)Wecannotignorethefactthat...f

　　2)Noonecandenythefactthat...

　　3)Thereisnodenyingthefactthat...

　　4)Thisisaphenomenonthatmanypeopleareinterestedin.

　　5)However,that’snotthecase.

　　8.表示比较

　　1)ComparedwithA,B...

　　2)IprefertoreadratherthanwatchTV.

　　3)Thereisastrikingcontrastbetweenthem.

　　9.表示数量

　　1)Ithasincreased(decreased)from...to...

　　2)Thepopulationinthiscityhasnowincreased(decreased)to800,000.

　　3)TheoutputofJulyinthisfactoryincreasedby15%comparedwiththatofJanuary.

　　10.表示看法

　　1)Peoplehave(take,adopt,assume)differentattitudestowardssth.

　　2)Peoplehavedifferentopinionsonthisproblem.

　　3)Peopletakedifferentviewsof(on)thequestion.

　　4)Somepeoplebelievethat...Othersarguethat...