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Topic : people in big cities are facing many health challenges due to a high level of air pollution. what causes air pollution in big cities? Can you suggest some ways to deal with this situation?

Air pollution is becoming more and more serious that makes citizens face up to the risks of health. This essay will discuss some possible causes of this problem and also suggest some hands-on measures to iron it out.
There are a bunch of factors that make a contribution to worsen the air quality. One typical factor is the emissions from private vehicles. Owing to the dense population in big cities, the number of vehicles commuting is increasing rapidly on a regular basis, which creates toxic gases filling in the atmosphere and being inhaled by the locals. Another contributing key is factories' gases. It is undeniable that the development of industry is at the expense of polluting the air terribly. Lastly, air pollution is also attributed to agriculture activities such as burning unwanted plant matter that easily add pollutants to the atmosphere.
There are, however, some feasible solutions that can be implemented to address air pollution. Firstly, the government should invest in upgrading the quality of private transportation and infrastructure in oder to encourage citizens warding off their private vehicles to use public ones. Moreover, they also need to bring in more regulations and penalties to punish people who handle their wastes wrongly. Besides, factories should be encouraged to relocate further away from the cities to prevent toxic fumes that threaten human's health. Last but not least, every indiduals need to enhance their awareness and become more eco-conscious to help tackle air pollution.
In conclusion, although air pollution is a tricky issue to tackle, nothing is impossible to deal with if everyone joins a hand to make much more efforts to enhance air quality.