英语语法分析

Legionnaires' disease is believed to occur worldwide.

一般认为，军团病在世界各地都可发生。

Untreated Legionnaires' disease usually worsens during the first week.

军团病不经治疗，通常在第一周期间恶化。

The first known outbreak of Legionnaires' disease was in Philadelphia, USA, in 1976.

军团病已知的首次爆发是在发是1976年美国费城，221人感染疾病，其中死亡34人。