成语反复无常用英语怎么说

中国人常说“言而有信”，意思是“A promise is weightier than one thousand bars of gold”。做出许诺就应该去实现，不应该“翻云覆雨”。

“翻云覆雨”，汉语成语，多指自己说了或做了，后来又反悔。比方言行自相矛盾，翻云覆雨，说话不算数（promise and then deny in succession;be inconsistent in one's words）。能够翻译为“go back on one's word”或“ renege on one's word”，表明“to break a promise that one has made；to not do something one said one would do”。

例句：

你容许支撑咱们的项目，现在却翻云覆雨！

You made a commitment to support our project, and now you've gone back on your word!

我气愤是因为你翻云覆雨！

I am mad at you because you reneged on your promise!

我不想翻云覆雨，可是我不会付你100美元的。

I hate to go back on my word, but I won't pay you $100.