How to make a nice kiss?

How to make a good kissing sound: (first, there must be a sweet sound, and then the sound must be lengthened when kissing) Sound, that is, the material shell of language, is the external form of language and a symbol system that directly records people's thinking activities. It is a sound with certain social significance issued by human vocal organs. The physical basis of pronunciation mainly includes pitch, sound intensity, sound length and timbre, which are also the four elements of pronunciation.