Why do so many people smoke? Some think that smoking is pleasure, some believe that they can refresh themselves by smoking. In fact, smoking is a bad habit, which has great harm to people'health. The study of smoking shows that many kinds of illnesses have something to do with smoking. Smoking itself is a waster. It costs one so much money, Besides, many fires are caused by careless smokers. Today more and more people all over the world want to give up smoking. If you’re mot a smoker, don’t start.