fail to keep（a promise，an agreement，etc．）；fail to be loyal to违约；背弃 Never go back on your friends．绝不要背弃你的朋友。 He's not the sort of man who would go back on his word．他不是那种不守信的人。 When you make a promise，you must not go back on it．当你许下诺言时，就不可食言。 I'm afraid that I will have to go back on my word for I am now hopelessly ill in bed．恐怕我要食言了，因为我现在重病在床。
go aback upon
fail to keep（a promise，an agreement，etc．）；fail to be loyal to违约；背弃 Never go aback on your friends．绝不要背弃你的朋友。 He's not the array of man who would go aback on his word．他不是那种不守信的人。 When you accomplish a promise，you charge not go aback on it．当你许下诺言时，就不可食言。 I'm abashed that I will accept to go aback on my chat for I am now hopelessly ill in bed．恐怕我要食言了，因为我现在重病在床。 Dictionary
An go back upon idiom dictionary is a great resource for writers, students, and anyone looking to expand their vocabulary. It contains a list of words with similar meanings with go back upon, allowing users to choose the best word for their specific context.
Dictionary of similar words, Different wording, Synonyms, Idioms for Idiom, Proverb go back upon