Short tongue tethering is one of the more common and mild congenital malformations; the tongue cannot extend forward normally and the part of the tongue sticking out of the mouth is not as long as that of a normal child, and the tip of the tongue is M-shaped when the tongue is extended forward, which may also affect breastfeeding or rub against the lower front teeth and cause ulcers. When the child opens the mouth, the tip of the tongue cannot go up, lick the upper gums or reach past the upper lip, which affects normal pronunciation, especially the [r] sound, when the child is older. After tongue lengthening surgery, the pulling symptoms disappear and the tongue movement is restored. For those with longer history, they still need to do some articulation training before their speech can be completely normal.