There is a white piece behind the tonsils, there may be several cases: the first case is food residue, because the surface of the tonsils is not smooth and flat, there are depressions that reach into the parenchyma called tonsil crypts. When the crypt is particularly large and deep, the food residue will be embedded in it, and after a long time, tonsil stones will form. The second case is the acute inflammation of the tonsil pus, pus moss is generally grayish white, this situation can be cured by anti-inflammatory and other symptomatic treatment, and tonsil pus, later pus moss is scattered, not just a piece. The third condition is tonsillar keratosis, which is a mucosal lesion that can occur in the tonsils and other mucosal locations in the pharynx. In this case, surgical removal is recommended because the keratosis will gradually develop and become more and more extensive, causing a foreign body sensation in the throat.