Since medieval times, it had usually been religious orders like the Sisters of Mercy who took care of the wounded.

自中世纪以来，照顾伤员通常由像仁慈修女会这样的宗教团体来负责。

I will join the Sisters of Mercy; I will tend the sick and the wounded.

我将加入慈悲修女会； 我会照顾伤病员。

She has looked after sick people ever since she was in short frocks, and does it better than any sister of mercy I know.

自从她穿着短裙以来，她就一直在照顾病人，而且做得比我认识的任何慈悲修女都好。