The first is the poor nasal ventilation in patients with obstructive sleep apnea hypoventilation, long-term open-mouth breathing, where the air does not enter through the nasal cavity but enters directly from the mouth in large quantities, leading to dry throat, foreign body sensation in the pharynx and other chronic pharyngitis manifestations. The second reason is to get cold during sleep at night and freeze, resulting in throat discomfort in the morning, especially for patients who usually have chronic tonsillitis and chronic pharyngitis, which may be more obvious. In the third case, patients may sleep at night in a place with air conditioning or in the north, where there is geothermal heating in winter, resulting in dry air or significant air temperature changes in the place where they sleep, which may easily trigger throat discomfort.