far public environment harmful smoke health Cigarette Pollution Cigarette smoking is one kind of pollution. It is the most (1) pollution in our lives and dangerous to our (2) . Smoking pollutes both the outdoor and the indoor (3) . Outdoors, besides fouling the air, it makes the streets dirty, for some smokers throw cigarette butts everywhere. However, the indoor environment is (4) more polluted. When you enter a meeting-room, you'll get a cough, because it is full of smoke and smells terrible. In a train, you'll find yourself covered with (5) if some smokers sit nearby. And you'll be unlucky if you share a room in a dormitory with a roommate who is a heavy smoker. So, let us work together to make more (6) places non-smoking areas.