With the     1    (develop) of industry, air pollution is getting more and more serious. In Beijing, many people suffer different kinds of illnesses because     2     air pollution.

Air pollution is caused by the following     3    (reason): about half of the problem is caused by vehicles. There are more and more cars, buses on the roads, and they give off     4    (poison) gases. 25% of air pollution is caused by factories. Another factor is the smokers. Smoking not only does harm to their health     5     to others.     6    (beside) these, about 10% of air pollution is caused by other reasons.

We should take some measures to fight     7     pollution. New fuel can be used to take     8     place of gas. We can plant more trees. If everybody realizes the     9    (important) of the environment and does something to stop pollution, the problem will     10    (solve)．