苦口婆心

媽媽苦口婆心地勸我好好讀書。

Mom earnestly advised me to study hard.

老師苦口婆心的教導，我們要銘記在心。

We should remember our teacher's earnest guidance.

他苦口婆心地說了很多，但她就是不聽。

He gave so much earnest advice, but she just wouldn't listen.