a？不是說:“在上（三）個世紀，由於引入了清潔水、抗生素和疫苗作為治療和預防多種傳染病的手段，預期壽命已大大增加”嗎?

來源: zillos 於 2021-05-20 14:36:44 [舊帖] [給我悄悄話] 本文已被閱讀：次

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