blunder

她在关键的发球上出现了失误，输掉了比赛。

She made a ___blunder on the crucial serve and lost the match.

他在演讲中犯了一个愚蠢的错误，把重要数据说错了。

He made a huge ___blunder during the speech by misquoting the key data.

在演讲中念错嘉宾名字真是个低级错误。

Mispronouncing the guest's name during the speech was a real ___blunder.