Does car do more harm than good？

China has such a large population, the popularization of private cars will bring out a lot of social problems. Some people have a view that car does more harm than good such as the traffic jam and the damage to the environment. 
Other people think the opposite way that car does more good rather than harm. With the popularization of cars, the suburbs will become more developed and the downtown areas will be less crowded. Using car is very convenient.
As far as my concern, the previous opinion is preferable in many senses (or cases). Several years ago, there were few cars so that people have no choice but to take a bus to go to work. However, an increasingly number of people would like to take a bus to go to work because of the heavy traffic. With the increasing number of cars, there are more and more traffic accidents occured in the world, especially in China. Besides traffic jams that produce harm, the most important thing is that the emission from the car contains a large volume of harmful gases. Some of the gases, such as the carbon monoxide and carbon dioxide, not only cause harm to human's health but also pollute the atmosphere.