Lung cavities take 10 days to 3 months to form; according to the common causes of staphylococcal pneumonia, tuberculosis, lung tumors and other causes. 1. The main clinical manifestations of staphylococcal pneumonia include fever, fatigue, chest tightness, chest pain, coughing and sputum, etc. In severe cases, lung cavities can be formed in 7-10 days; effective antibiotics such as levofloxacin are used for treatment. 2. Clinical manifestations of pulmonary tuberculosis include coughing up blood, fatigue and night sweating, low fever in the afternoon, etc.; if the condition is not controlled in time, cavities can be formed in about 3 months; treatments include anti-tuberculosis treatments such as isoniazid and rifampicin. 3. Clinical manifestations of lung tumors include fatigue, loss of appetite, cough and sputum, weight loss, etc.; generally, cavities are formed in 3 to 6 months; early surgical treatment. There are many other reasons that can lead to lung cavity, such as fungal infection, vasculitis, etc. It is recommended that patients go to regular hospitals and complete relevant examinations in time.