to flog a dead horse
01
to waste time and energy on something that cannot be changed or revived
Dialect
British
British
![to [flog] a dead horse definition and meaning](https://cdn.langeek.co/photo/40835/original/?type=jpeg "to [flog] a dead horse definition and meaning")
例子
We've revised that proposal three times; pushing it again feels like flogging a dead horse.
to waste time and energy on something that cannot be changed or revived
British
