on the battlefield

基本解释

One should never succumb to fatigue when alone on the battlefield.
一个士兵永远不该在战场上屈服于困倦。
The laser also can flexibly support missions on the battlefield as well as in urban operations.
激光器还可以在战场上或在城区中灵活地支持作战任务。
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They often separate the good from the bad (and ugly); and, on the battlefield, the living from the dead.
它们常常能从恶（和丑陋）中分离出善；并且在战场上能决定生死。

The human remains were moved from other places on the battlefield and put into graves in the new cemetery.
That is, this kind of aristocratic outfit, aristocracy of birth, which is legitimized by heroic behavior on the battlefield.
也就是说,由于他们在战场上的英雄行为,他们的贵族的身份和贵族出身是被认可的
耶鲁公开课 - 古希腊历史简介课程节选
The question is would the defeated army- would the winning army kill all the defeated guys who were still on the battlefield at the time?
你问的是战败军,胜利的一方是否会杀死,战败但仍在战场上的敌人
耶鲁公开课 - 古希腊历史简介课程节选

You know, the entire country, certainly, of Iraq and even Afghanistan is basically on the battlefield.
NPR: Women in Combat: Rules and Reality