speak too soon

to say something that is quickly shown not to be true

过早下结论

He won't be home for hours yet ... Oh, I spoke too soon - here he is now!

他一时半会儿还不会到家……哦，我这话说得太早了——他回来了!

I was certain Nina would fail at her task and said so boldly. When she successfully completed her task, I knew I had spoken too soon.

我确信尼娜的任务一定会失败，所以大胆地说出了这些话。当她成功地完成了她的任务，我知道我言之过早了。