Our modern city is very crowded and to solve the problem,three proposals are put forward.First,the policy of late marriage is advocated and a couple has only one child so as to reduce the birth rate and take control of the population growth.Second,in order to lighten the pressure of the extraneous population on cities,the government should strictly take proactive control of outlanders who enter cities to work or get engaged in business .Finally,life,business,culture,education,health,recreation and leisure living blocks and satellite cities should be built in suburbs so that city citizens can be absorbed to live and work there.If the proposals are well carried out the population will be greatly reduced