fall flat on your face
US /fɔl flæt ɑn jʊər feɪs/
UK /fɔl flæt ɑn jʊər feɪs/

1.
彻底失败, 栽跟头
to fail completely or to be unsuccessful in an embarrassing way
:
•
His grand plan to impress the boss fell flat on its face.
他想给老板留下深刻印象的宏伟计划彻底失败了。
•
The comedian's new jokes fell flat on their face with the audience.
这位喜剧演员的新笑话在观众面前彻底失败了。