friend and foe

基本解释

BACTERIA, like people, can be divided into friend and foe.
细菌和人一样也有敌我之分。
Ozone is a chemical that can be both friend and foe to human beings — depending on where it is.
臭氧是一种利弊两全的化学物质。是利是弊，这得看它在哪儿出现。
The lack of information on his condition led many, both friend and foe, to assume the worst.
由于缺乏关于他健康状况的资讯，造成很多人士（无论敌友）都以为发生了最坏状况。

One of the most difficult things in life is to draw the line between friend and foe.
CENTERFORSECURITYPOLICY: Telling friend from foe
Excerpt: As friend and foe alike recognised at the end of January 1806, Pitt had bestridden a confusing and rapidly changing world with authority.
FORBES: Fact and Comment
Players can choose to build friendly relationships with other cities or form an intense rivalry through a dynamic and ever-evolving friend and foe system.
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