The swallowing action is divided into 3 phases: oral, pharyngeal and esophageal. The evaluation of ingestion-swallowing disorder is generally divided into the following 6 phases. 1. Awareness of food is the stage before food is introduced. Patients with low level of consciousness have no reaction even when they see food; those who cannot concentrate mentally and are indifferent to food are very likely to swallow by mistake when eating. 2.Fine food The mouth, lips and front teeth are coordinated to adapt to the shape of food and tableware to incorporate food into the mouth. Patients with poor lip closure cannot smoothly incorporate food into the mouth. Even if food is fed into the mouth, it often leaks out. In the oral cavity, food is mixed with saliva to form a shape that can be easily swallowed (food mass), and its formation varies depending on the shape of the food. Liquid food is easy to swallow; semi-liquid food such as jelly and porridge needs to be formed by “pushing and chewing” (the tongue body moves up and down so that the food is pushed and squeezed between the tongue and the hard palate); solid food needs to be “crushed and chewed” in addition to “pushing and chewing”. In addition to “pushing and chewing”, solid food also requires “grinding and chewing” (the tongue body moves from side to side to grind the food on its own teeth) to form food blocks. When chewing, the lower jaw does up-and-down and gyratory movements, at which time the soft span is closed between the root of the tongue and the tongue (the isthmus) to avoid food entering the pharynx. If the chewing movement, the formation and maintenance of the food block cannot be successfully completed, the food is either swallowed whole or flows into the pharynx before the swallowing reflex is induced. 4.Food enters the pharynx (oral phase) After chewing is completed, the tongue is lifted up and the food block is pushed along the hard palate from the tip of the tongue to the root of the tongue to reach the site where the swallowing reflex is induced, and then the lips of the mouth are closed and the jaw is fixed, and swallowing occurs. If the food block cannot be sent to the root of the tongue smoothly after chewing, the patient can be asked to tilt his head back or lie on his back to use the effect of gravity to promote the arrival of the food block at the root of the tongue into the pharynx. 5, the food block through the pharynx (pharyngeal phase) food block against the pharynx, the soft crotch and eccrine respectively blocked the part with the nasal cavity, tracheal access, causing a momentary swallowing respiratory arrest, at the same time, the tongue to the posterior wall of the pharynx to push pressure, the pharyngeal wall peristalsis, the food block into the esophagus. This process is called the swallowing reflex, which takes about 0.5S to complete in normal people. misopharynx is due to weak swallowing action, incomplete swallowing of food, residual food in the pharynx entering the trachea during breathing, or due to dysfunctional swallowing reflex action and incomplete tracheal atresia. 6, food block through the esophagus (esophageal phase) After the food block enters the esophagus, the negative pressure in the esophagus makes the food fast not work along the esophagus into the stomach.