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来源：雅诚德英语网
The air then passes through the larynx and down the trachea. The trachea splits into two tubes, called the primary bronchi. One bronchus passes into each lung.
接着空气通过喉下至气管，气管分为两根，称为主支气管，每一根主支气管通入一叶肺。
The air then passes through the larynx and down the trachea. The trachea splits into two tubes, called the primary bronchi. One bronchus passes into each lung.
接着空气通过喉下至气管，气管分为两根，称为主支气管，每一根主支气管通入一叶肺。