A: His parents and teachers scolded Peter, but it was like water off a duck's back.
B: The criticism fell on deaf cars.
A: He's beyond help.
B: We should try our best to help him.
like water off a duck's back
exp. Without any apparent effect. （没有明显的效果）
e.g. I was worried losing his job was going to trigger his depression, but it seemed to roll off him like water off a duck's back.
e.g. I envy my sister because any criticism or judgment is like water off a duck's back to her.
e.g. I kept telling the boys not to bang doors but is was like water off a duck’s back.
e.g. The doctors tell us it’s dangerous to smoke but such good advice rolls off some people like water off a duck's back.
1. fall on deaf ears：没有被听取，未被理睬
exp. To be ignored
e.g. Her pleas for mercy fell on deaf ears; the judge gave her the maximum sentence.
e.g. All of Sally's good advice fell on deaf ears. Walter had made up his own mind.
e.g. The mayor spoke privately to Gibbs yesterday and asked him to resign, but his plea fell on deaf ears.
2. beyond help：无可救药，无法帮助，无法挽救
e.g. Don't waste your breath talking to him, he's beyond help.
e.g. The dying man is beyond help.
3. try one’s best：尽力
e.g. I try my best, but the coach finds fault with everything I do.
e.g. We must try our best to lay his doubts.