The thickening of the two lower lung textures mostly suggests changes of acute and chronic bronchitis, but also includes bronchial asthma, chronic obstructive pulmonary disease, and long-term recurrent attacks causing thickening of the lung texture. Once the chest CT or chest X-ray suggests thickening of the two lower lung textures, it is mostly considered to belong to the changes of bronchitis, and of course also includes patients who have been smoking for a long time, as well as bronchiectasis, old tuberculosis, pulmonary fibrosis and other diseases, which can also cause thickening of the lung texture. The thickened lung texture may not have clinical manifestations, but may appear after cold or flu with mild cough and sputum, which is considered to be bronchitis with infection, depending on the situation to see if antibiotics and herbal treatment are needed. In conclusion, the thickened texture of the two lower lungs mostly indicates changes of bronchitis, without considering lung tumors, tuberculosis, pneumonia and other conditions.