Main idea: 

First, we need to volunteer of environmental activity in our free time instead of playing game, wasting time.

Secondly, we will tell the truth to our family, friend about the affection of air and water pollution. So that, they can know that information and share it for thier friend, family to reduce the pollution in our city.

Third, we can create many environmental activities in social network to reduce air and water pollution in the city. Everyone who participate in these activities, will clean our city. 
Nói chung thì nhiều ý lắm ví dụ: Participate in game show which can discuss with the government about the pollution in your city.

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