With the development of industry, air pollution is getting more and more serious. In this city, many people

suffer from different kinds of illness because of air pollution.

     Air pollution is caused by the following reasons. About half of the problem is caused by vehicles.There are

more and more cars and buses on the road, which give off poisonous gases. 35% of air pollution is caused by

factories. Another factor is smoking. Smoking does harm to others'health as well as to that of the smokers.

Besides, about 10% of air pollution is caused by other reasons.

    We should take some measures to fight against pollution. New fuel can be used to take the place of gas.We

can plant more trees, grass and flowers. All in all, if everybody realizes the importance of environment and

does something to stop pollution, the problem will be solved.

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