Pneumonia most often causes dyspnea, or shortness of breath, chest pain, and a productive cough, meaning that pus or bloody sputum might come up.

肺炎最常引起呼吸困难、呼吸短促、胸痛和排痰性咳嗽，这意味着可能会出现脓痰或血痰。

These two are different in that chronic bronchitis is defined by clinical features, like a productive cough, whereas emphysema is defined by structural changes —specifically enlargement of the air spaces.

区别于肺气肿，慢性支气管炎有明显的临床特征，例如排痰性咳嗽，而肺气肿以结构改变为主，具体来说就是气腔的扩大。