1, take a deep breath of smoke, let a lot of smoke be stored in the throat, remember not to inhale; Then lower your tongue, open your mouth and keep your lips O-shaped. It must be round, and the opening should be controlled, not too big.

2, the tongue shrinks backwards, the tip of the tongue should droop naturally, and then put it under the lower gum; The tip of the tongue is lifted and bounced back to send out the cigarette in the mouth; Adjust your lips to change the size of the smoke ring, and you can spit it out.

The formation of smoke ring is caused by the annular air vortex that confines smoke particles in the annular area. When smoke particles quickly pass through a circular hole with air, because the air around the outlet of the circular hole is still, the air-particle mixture flowing out of the circular hole will drag the static surrounding air, thus forming a vortex rotating from the edge of the hole to the inside.

Extended data:

20 14 12.4, Reuters published an article entitled "Scientists find that smoking men face greater health risks", saying that a research report published by researchers from Uppsala University in Sweden in the American magazine Science said that compared with men who have never smoked or given up smoking, the Y chromosome, which is crucial for determining sex and producing sperm, often disappears from the blood cells of smoking men.

Since only men have the Y chromosome, this discovery can also explain why smoking is more carcinogenic to men than to women. Jan Dumanschi, a professor at Uppsala University who participated in the study, said: "The disappearance of Y chromosome, the most common mutation in human body, has something to do with smoking."