Weliveintheworldeveryday.Weeatfood,drinkwater,wearclothes,watchTV,usecomputersandsoon.Weareproducingwasteeverymoment.

　　Generallyspeaking,therearefoursortsofwaste.Theyarematerialwaste,organicwaste,inorganicwasteandpoisonous&harmfulwaste.Now,wearegoingtotalkabouteachsortofwasteonebyone.

　　Materialwaste:itmeansthewasteofsubstanceorthingsfromwhichsomethingelsecanbemade.Forexample,peoplethrowawaytheusedmetalproductsandbuyanewone,sotheoldmetalwasteaccumulates.Atlast,theybecomewaste.Forexample,whenpeoplefinishreadingnewspaper,thepaperwillbecomewaste.Whentheglassisbroken,italsobecomeswaste.Nobodywantstouseabrokenwindowordrinkwithabrokenglassorwearapairofbrokenglasses.Onceitisbroken,itbecomeswaste.Therateofusingplasticsisincreasingdaybyday.Peopleuseplasticbagsbecausetheyareconvenient.Whentheygethome,theythrowtheplasticsway,payingnoattentiontotheenvironment.Themoreconvenienceplasticsbringstous,themoreplasticwasteisproduced.Thisiscalled“whitepollution”asmostplasticsarewhite.Someofourproductsweuseeverydayaremadeofrubber,justlikethetyresandthebottompartofourshoes.It’struethatrubberplaysanimportantroleinourlife.However,italsobringsussometroublewhenithasbeenusedforalongtimeandbecomesold.Theoldtyresbecomewastebecauseitcan’tbreakdownbynature.Thisisreallyabigproblem.

　　Organicwaste:itreferstowastefromlivingthings,includingwastefromanimals,plantsandpeople.Somepartsofvegetablesarethrownawayaswastebecausetheydon’ttastegood.Inthepast,peoplecookedtheirfoodusingburningcoal,sotherelefttheburnedcoal,whichisuseless,likethethrownvegetables.Allthissortsofwastecontainorganism,soitiscalledorganicwaste.

　　Actually,wealsohaveinorganicwaste,theoppositetoorganicwaste,includingbuildingwaste,brokenpotteryandchina,andcinder.

　　Thelastpartisharmfulandpoisonouswaste,suchasusedbatteries,electricalapparatusandmedicalsupplies.ComputersandTVsetsareonepartofelectricalapparatus.Yousee,theoldelectricalapparatuscansetoffsomedangerousraysandmakethesoilharder,evendamagetheundergroundwater.MobilephonesareasdangerousascomputersandTVsets.Asweknow,X-rayscanbeusedtoexaminepatients,buttheX-raysmachinesaredangerouswhentheyarethrownawaywithoutanytreatment.Theycan’tbeusedtotreatthesick,buttheystillcangiveoffrays.Forthenormalpeople,theycanbedangerous.So,wemustthinkaboutthisproblem.

　　Aswastehasfoursorts,wecansortthemintoeachsortthattheybelongto.It’sconvenienttotreatthemaftertheyaresorted.Thenwecandealwiththemsortbysort.Wehavethoughtoutsomemethodslikestoringtheminordertochangethemintoplantfood,orburningtheminahugestoveandusetheheattomakeelectricity.Forthefirstway,thechangerateismuchtoolowanditmaypollutetheundergroundwater.Forthesecondone,ofcourseit’swonderfulifit’seasytobetriedout.Buttobuildsuchahugestovewillcosttoomuch.Notagoodmethod.Nowyousee,treatingwasteisnotaneasyjob.

　　Fromwhathasbeendiscussedabove,wecandosomethingtoourhome—theearth.Weshouldmakefulluseofthings.Atthesametime,we’