Xiao is a very old Han musical instrument with single pipe and vertical blowing, which can be divided into harmony. Xiao has a long history, mellow and soft timbre, quiet and elegant, suitable for solo and ensemble. Generally, it is made of bamboo, with pores at the upper end. According to the number of "sound holes", it is divided into six-hole flute and eight-hole flute. The sound holes of the six-hole flute are the first five and the last, and the eight-hole flute is the first seven and the last.

Basic methods of oral sex:

1. Place the flat end of the flute pipe at the same height as the mouth, and the blowing hole is located at the upper side;

2. The lip is slightly closed, that is, the air hole is close to the lip seam, and the tip of the upper lip contacts the semicircular outer edge of the air hole to determine the position of the air hole;

3. Hang the tail of the flute slightly (at an angle of about 45 degrees with the horizontal plane), support the top of the flute with the lower jaw, and completely cover the cross-sectional gap of the blowing hole with the lower lip, but it is not necessary to stick tightly;

4. Keep your lips loose, and squeeze the corners of your mouth inward and toward the center (be careful not to stretch them too tightly, and don't close your upper and lower teeth) to form an oval (or diamond) narrow gap between your lips.