Dry tobacco is the oldest tobacco product in China. A variety of sun-cured tobacco is made by moistening leaves, tabletting and shredding. And ground single sun-cured tobacco. For Europeans, the history of tobacco development began at 1492, but the entry of tobacco into human society began in primitive society Latin America. As early as 4,000 years ago, the Mayans living in Mexico today began to grow and smoke tobacco. At that time, Latin Americans were still in a period when gathering and hunting were the main production activities. When people pick and taste plants, they can taste the spicy tongue of tobacco with intoxicating aroma, which can refresh themselves and be used as stimulants. But the more times you chew, the more you gradually become a hobby. The cultivation and smoking of tobacco has taken the first step in human life. The roots and stems of tobacco contain nicotine, which is translated as "nicotine". It is a colorless or yellow volatile oily liquid that can be mixed with water in any proportion. Nicotine first excites the nerves of animals, and then paralyzes them. It can be used as an insecticide to prevent aphids and lice. Generally, tobacco leaves can be directly sprayed in water. It should be noted that nicotine is very toxic to people and animals, and the nicotine extracted from a cigarette is enough to kill an adult bull. Excessive smoking can cause vascular injury, respiratory mucosa inflammation and may also induce lung cancer. Teenagers are developing, so smoking should be stopped. ?