-who pollutes the air the most?
-what happens when the smoke from the factories reaches the air
-what is air pollution
-it's good that we're polluting the air
-is smoke in the air helpful?
-do cars pollute the air?
-do factories pollute the air?
-how cars pollute the air
-Is it hard to pollute the air or take care of it?
-where does the smoke that pollutes the air come from?
