save your breath
used to say that it is not worth talking to someone because they will not listen to you
不值得浪费口舌;不必对牛弹琴
I don't know why I even try to talk to him - I might as well save my breath.
我不知道为什么要费口舌和他说话——最好还是不要对牛弹琴。
A: Matt's work is such a mess! I think I need to talk to him about it.
马特的工作真是一团糟!我觉得得跟他谈谈了。
B: You might as well save your breath. He just doesn't listen to reason.
你就别白费口舌了,他压根就不听劝。
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