I hate to go back on my word, but I won't pay you $100 after all.
•Going back on your promise makes you a liar.
Смотреть больше слов в «Dictionary of American idioms»
go back on one's word: translation go back on one's word & go back on one's promise & go back on one's pledge to break a promise that one has made. • I... смотреть
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