this reading talking about the Pm2.5 on the earth. The air pollution is always a hot topic in China and Chinses people are all concern about this problem. Because it will caused a lot of health problems even will threaten people’s life. When we see the image we can clearly see that most of the Asian country have a serious polluted problem. However, I think it’s unavoidable .because those countries are all developing and they need the factory to help them to grow. Also American is the cleanest air country is also because it’s a developed country a lot od their factories choose to move to those developing countries. From my perspective, only if a country becomes strong, they can have the power to change the environment and it’s an unavoidable problem for all the country wants to develop.