题目内容：

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 following3._________: 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._________ 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 environment and does something to stop pollution, the problem will10.__________（solve）.