four: don't pour the rubbish into the river.
though these are small things to protect water, i still thin they're important.airpollutionisoneofthemajorproblemsofthemodernworld.agreatdealofenergyisneededtorunthefactoriesofmodernindustrialnations.
automobile,trains,planesandbussesneedenergy,too.nearlyallofthisenergyisproducedbyburningfuels.theburningproduceswastes
,someofwhichremainintheair,causingairpollution.
scientistsarefindingwaystostopairpollutionespeciallyinbigindustrialareasanddensely-populatedcities.theyarestudyingnewwaysofgeneratingelectricitythatmaybelessdamagingtotheenvironment.inthemeantime,
manypowerplantsarebeingmodernizedtogiveofflesspollutedmaterial.
also,engineerstrytodesignandlocatenewpowerplantstodominimumdamagetotheenvironment.
however,itmaybethatwestillhavealongwaytogobeforewehavea"clean"world.
nearlyallofthecountriesaretryinghardtopreventandcontrolairpollution.
thereindeedseemstobenoendtotasksthatenvironmentalistswillberequiredtodo.peoplewillcontinuallyfindnewwaystocontrolpollution.
pollutionisbecomingmoreandmoreseriousallovertheworld.asisshowninthecartoon,t
wocarsaregivingoffwastegasandthreepeoplearetryingtoavoidbreathinginthepoisonousgasbymaskingtheirfacewiththeirhands.
thepoisonousgassentoffbyfactories,domesticappliancesandautomobileshasmadetheairunhealthyforpeopletobreathe.
thereisnodenyingthatautomobilesareindicationsofcivilization,progressanddevelopment;nevertheless,
automobilescausetheseriousproblemofairpollution.scientistshavewarnedthatunlesseffectivemeasuresaretaken,
theproblemofpollutionwilleventuallygetoutofhand.actually,peopleareshowingarealconcernovertheproblem.
forexample,thereisanincreasinglyloudvoicefromthepublicforfirmactionagainstpollutionfromautomobiles.
indeed,theearthisourhomeandwehavethedutytotakecareofitforourselvesandforourdescendants.inmyopinion,
weshouldworkoutconcretesolutionstotheproblemofpollutionfrompoisonousgasgivenoffbyautomobiles.
forexample,theautomobilesshouldbeequippedwithadevicewhichcandisposeofwastegassoastopreventitfrompollutingair.
onlyinthiswaycanwereallysolvetheproblemofairpollutioncausedbyautomobiles.