出处：按学科分类—语言、文字 中国对外翻译出版公司《汉英成语词典》第276页（245字）
指说话不算数，例商场交易首重诚信，若是言而无信，出尔反尔，则不仅商誉扫地，亦必将为人所耻笑。
In market transactions，honesty is of primary importance．If promises are not kept，one's reputation will suffer and one will be also ridiculed by all．