一言既出，駟馬難追 [ㄧ ㄧㄢˊ ㄐㄧˋ ㄔㄨ , ㄙˋ ㄇㄚˇ ㄋㄢˊ ㄓㄨㄟ; yi1 yan2 ji4 chu1 , si4 ma3 nan2 zhui1] lit. once said, a team of horses cannot unsay it (idiom); a promise must be kept ◄ ►
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