Nowadays PM2.5 and other problems has become a problem we have to see. As is known to us that once the balance in nature is disturbed, it can lead to unpredictable results. Many factors that contribute to it. Firstly, merchants only pay attention to profit. So we should protect the environment and coordinated economic development. Secondly, the cars in China increasingly raise. We all know off gas can pollute air deeply. So we should suggest people that go to work by bike or bus. Thirdly, wasting water and excessively cutting down trees is increasingly common. I think we should suppose environmental protection knowledge. We should spare no effort to protect our environment. 

Only in this way can we solve pollution problems. I believe nothing in the world is difficult for one who sets the mind to it.