The swollen left tonsil is mainly seen in the following: 1. Repeated inflammatory stimulation of the tonsils, resulting in swollen left tonsil, mostly seen in children, but also in adults. When questioned about the medical history, patients are informed that usually the tonsils are often inflamed, and the surface of such inflammatory swollen tonsils is relatively smooth, and there is no special abnormality when they are not inflamed, just swollen tonsils. 2. Painless swollen tonsils, which may be Tonsillar lymphoma, mostly seen in middle-aged and elderly patients, usually without recurrent inflammatory stimulation of infection of the tonsils, is mostly found during physical examinations with painless unilateral enlargement of the tonsils, possibly accompanied by enlarged lymph nodes in the neck. In this case, it is recommended to do lymph node biopsy to clarify the pathological nature.3. Cancer of the tonsils, commonly known as tonsil cancer, the surface of such tonsils is generally not smooth, there may be ulcers, and there may be neoplasms, local biopsy can clarify tonsil cancer, squamous tonsil cancer is more common.