What is done can't be undone!

木已成舟！

youdao

What is done cannot be undone, you know.

你知道，覆水难收。

youdao

What is done can't be undone, and I must be patient!

覆水难收，我必须有耐心！

youdao

He says the poet shows a married couple suffering from things done and undone.

VOA: special.2010.04.05

He said poor supervision had led to "work left undone or done messily".

BBC: Travellers at the Beijing West Railway Station, Jan 2013

Because what we have done and what we have left undone in thought, word and deed on a national level determines as much as anything else the margin of safety that a prudent investor should require to invest in that nation.

FORBES: Magazine Article

Unfortunately, based on my research and experience, this obvious step is too often left undone or, at least, not done well.

FORBES: Spend A Little To Learn A Lot