1, faithless: pinyin yá né rú xì n
The explanation is that you don't keep your word and have no credit.
The source "Gu Liangchuan Xi Gong Twenty-two Years": "The reason why the words are spoken is because of the letter; If you don't believe it, why say it? "
Synonyms don't believe words, Break one's word
Antonym? It's a deal, a promise is a promise, a promise is a promise.
One should keep his promise and never break it.
2, eat your words: Pinyin zü shí qí yá n]
That means you don't keep your word, you don't keep your word.
The source "Shangshu Tang Shi": "I believe everything and will not break my word."
Synonyms don't believe words, Break one's word,
The antonym is promise, promise is promise, and a word is promise.
If you promise to help, you shouldn't break your word.