鞠躬尽瘁 to give the last measure of devotion
聪明反被聪明误 to suffer for one's wisdom
旧调重谈 to harp on the same string
礼尚往来 Courtesy on one side cannot last long.
礼多必诈 full of courtesy, full of craft
声嘶力竭 He was talking at the top of his voice.
覆水难收 What's done cannot be undone./There is no use crying over spilt milk.
转石不生苔 A rolling stone gathers no moss.
转败为胜 to convert defeat into victory
小Car笔记：
courtesy：礼貌, 好意, 恩惠 【常用短语】①courtesy light：礼貌灯, 门控车室照明灯 ②courtesy title：礼貌性的尊称