Don’t waste your breath; he won’t listen.

别费口舌了，他不会理你的茬儿。

To reason with a person without shame is just to waste your breath.

跟一个赖皮讲道理是白费口舌。

It would be a waste of your right to speak if you don’t speak out, and it would be a waste of your breath if you do.

不说白不说，说了也白说。

No, i won't agree! don't waste your breath.

不，我不会同意的。别跟我这儿费口舌。

He won't listen, so don't waste your breath on him.

他不会听你的，别枉费唇舌了。

It‘s no use talking to him ,you‘ll only waste your breath。

和谈谈话没有一点用处，你只是在白费唇舌。

Don't waste your time and breath. It's not worth casting pearls before swine!

别浪费你的时间和精力了，不值得和他对牛弹琴！