What a palaver there was about paying the bill!

事真费舌呀!

Save your breath to cool your porridge.

不要白费舌了。

In making that plea he will breathe in vain.

他做那种恳求是白费舌。

They tried in vain to persuade her to go.

他们极力劝她去，但枉费了一番舌。

It was mere waste of breath to argue with a person in so unreasonable a state of mind.

与一个如此不讲道理人争论纯粹是浪费舌。