p; teeth bit the upper lip lightly,
Gently suck your lower lip,
The saliva is lightly rubbed on the upper and lower lips,
then suck clean,
Tongue and tongue push and twist each other,
Hold your tongue with your lips and gently suck the tip of your tongue,
Use the tip of your tongue to carefully explore the inner and outer sides of the gums,
Slowly stimulate the mucous membrane of the mouth,