Sometimes a person fights a battle that has been decided or keeps arguing question that has been settled . We say this is like a beating a dead horse.

有时一个人对抗一个已经决定或已经得到解决的争论问题。我们说，这像是打一匹死马。

youdao

Still dead quiet in the kitchen except for renewed clanking and scraping and the beating mixer again.

厨房里仍然是一片静寂，但很快就再次响起了叮当声、刮擦声以及敲打搅拌器的声音。

youdao

Do you think it's worth me writing to a few more recruitment agencies, or am I just beating a dead horse?

你觉得我再给一些藾招聘公司写信值不值？还是我只是在浪费时间？

youdao

We say this is like beating a dead horse.

VOA: special.2009.07.12

Most organs are donated from a patient who has been declared brain stem dead, but whose heart is still beating.

BBC: New powers call for donor cards

The long-term hope is to treat patients with some sort of stem cell that could turn into beating heart muscle and replace dead cardiac tissue with fully functioning new cells.

FORBES: Using Thigh Muscle To Fix The Heart

Novak Djokovic's Serbia will play either the U.S. or Brazil after beating Belgium 3-2, having lost Sunday's two dead rubbers as the world No. 1 and Viktor Troicki were rested.

CNN: Nadal: I must be humble in comeback