work hard play hard的意思是努力工作努力玩。hard主要用作为形容词、副词、名词，作形容词时意为“努力的；硬的；困难的；辛苦的；确实的；严厉的；猛烈的；冷酷无情的”，作副词时意为“努力地；困难地；辛苦地；接近地；猛烈地；牢固地”，作名词时意为人名。
例句：
Why do they have to work so hard?
他们为什么工作必须那么努力。
Every one of us should work hard for the prosperity of our country.
我们每一个人都应该为我们国家的繁荣而努力工作。
I find it hard to trust not only me, but everyone around me, Because of.
因为你，我发现很难再相信我自己以及周围的每一个人。
The ground is as hard as stone after the long drought.
长期干旱之后，土地硬得就像石头一样。
It&39;s very hard to maintain a relationship.
要维持一段关系，是很困难的。
It&39;s very hard on parents when their children are rebellious.
对父母来说，孩子叛逆是个很棘手的问题。
