pollution: beijing is one of the most polluted cities in china. due to its location, which is close to inner mongolia, the city suffers from sandstorms from time to time. however, more serious consequences were caused by the chemical factories situated in the suburban areas of beijing and exhausted gas emitted by automobiles. in 2016, the air quality of only 198 days was marked “non-polluted”, and the air quality of 39 days was considered “seriously polluted”, with pm2.5 being the main pollutant. up till now the local government still hasn’t taken sufficient measures to control air pollution, which poses a big problem for people’s health.