main bronchus

例句：

1. 1. The doctor performed a surgeryon the patient's main bronchus to relieve his breathing difficulties.
   医生对患者的主支气管进行了手术，以缓解他的呼吸困难。
2. 2. Main bronchusblockage can lead to serious respiratory problems.
   主支气管阻塞可能导致严重的呼吸问题。
3. 3. Duringthe operation, the surgeon carefully removed theblockage from the patient's mainbronchus.
   在手术中，外科医生小心地从患者的主要支气管中移除了阻塞物。