Traffic problems have become one of the major problems in cities. Streets are always crowed with vehicles and pedestrains, especially in rush hours. What is more, traffic accidents have made streets become one of the most dangerous places. But why is this problem becoming more and more serious in spite of the continuous improvement of traffic facilities?

　　The rapid increasing population is a goot explanation of the answer. More people means heavier traffic. Moreover, because more space has to be used to meet the needs of the housing problem, it is almost impossible to widen the streets, which makes the situ ation even worse. Then, how can we solve this problem?

　　More measures should be taken to deal with this problem. For example, rigid rules and regulations of rewards and penalties should be established to make people more careful on the streets, in addition, much more efforts should be made to put the population planning policy into practice.