To waste one's breath or words; to talk in vain; to argue fruitlessly.
他试图劝说固执的朋友改变主意，但最终只是徒费口舌，毫无效果。
He tried to convince his stubborn friend to change his mind, but in the end, it was just a waste of words, with no effect.
Era:
Early Modern
Frequency:
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