白费口舌

waste one's breath; waste one's words; whistle down the wind

1. 老师发现他是在白费口舌；孩子们根本不相信他。
   The teacher saw that he was wasting his breath; the children refused to believe him.
2. 他谁的话都不听，你只是在白费口舌。
   He won't pay attention to anybody. You're just wasting your breath.

白费的英语翻译：

口舌的英语翻译：