about 15 minutes and that chain smoking is far more hazardous. Recent findings of medical research show that even a tiny drop of nicotine (about 3 grams in weight) can kill a large animal like a horse. Some medical reports have also proved that heavy smoking would seriously affect an adult’s sexuality, and smoking after a meal also disturbs one’s digestive system. Cigarette smoking not only jeopardizes the physical health of a smoker, it also affects the health of a nonsmoker who passively inhales the polluted air into his or her lungs when he or she is exposed to a winding shroud of cigarette smoke. The impact on such passive smokers (also called second-hand smokers), according to the experts in the medical field, can be even more damaging, and that is why smoking is usually prohibited in most public places. (211 words)