书面表达练习近年来，城市空气污染越来越严重，各大城市相继出现了雾霾天气（hazyweather），请根据下列内容要点提示，写一篇关于保护环境的文章。内容要点：1.雾霾成因：①汽车使用增加；②工厂污染严重；③树林大量砍伐2.建议办法：①尽量少用私家车，选用公共交通工具、步行或骑自行车；②(自拟1—2条)写作要求：1.词数80左右；2.短文必须包含所有要点，可适当发挥。Theseyears,airpollutionisgettingworseandworseinbigcities._____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ 参考范文Theseyears,airpollutionisgettingworseandworseinbigcities.Nowcarsareincreasingveryfast.Factoriesarecontinuingpollutingtheair.Treesarebeingcutdown.Sothehazyweatherisbecomingmoreandmoreserious.It’stimeforustodosomethingtoprotecttheenvironment.Firstofall,we’dbetternottravelbycarunlessit’snecessary.Wecantakethebusorthesubway,walkorrideabikeifwedon’tgofaraway.Wecanalsosetupavolunteerclubandaskmorepeopletojoinit.Wecanplantmoretrees,givethegovernmentadvicetostopthefactoriespollutingtheairandwater.Inaword,protectingtheenvironmentistoprotectourselves.It’sourdutytoprotectourenvironment.