to save one's breath
01
言っても無駄, 話しても仕方ない
to avoid wasting one's time and energy by not trying to persuade or convince someone who is unlikely to change their opinion or behavior
![to [save] {one's} breath definition and meaning](https://cdn.langeek.co/photo/40965/original/?type=jpeg "to [save] {one's} breath definition and meaning")
例
Save your breath; he won't listen.
言っても無駄だよ。彼は聞かない。
言っても無駄, 話しても仕方ない
言っても無駄だよ。彼は聞かない。
