Trafficcongestionhaslongbeenaproblemofgreatconcernandcomplaintinbigcities.Ithascausedalotofinconveniencetopeople'slifeandwork.Forexample,peoplehavetosetoffwellinadvancetogettoworkontimeandcomebackverylatewhentheirworkisover.Therearemanycausesforthisproblem,butthefollowingmaybethemostimportantones.Thefirstcauseisthegreatincreaseinthenumberofprivatecars.Carstakeupmorespacebuttheycarryfewerpeople.Someprivatecardrivers,ignoringtrafficregulations,driveonlyforthesakeoftheirownconvenience,blockingthewayofotherpublictransportationvehicles.Thesecondcauseistheslowandinefficientconstructionandimprovementoftheroadsandstreets.Withalargepopulationandnumbersofautomobilesincreasing,someroadsstillremainunimproved,whichwillsurelyleadtoproblems.Thelastcauseistheinsufficientmanagementofthetrafficsystemandthepeople'slackofawarenessoftrafficregulations.Manypedestrianscrossthestreetsevenwhenthetrafficlightsareagainstthem,whichisanobstacletotheflowoftraffic.Theproblemoftrafficcongestionisanurgentonebecauseitconcernsthesafetyallofus.Wewillnotresolveitifweonlyrelyonthegovernment.Letallofusactnowtosolveit.