until the cows come home
直到很晚（常指深夜或凌晨），很久很久
口语·形容时间极长
英文释义
for a very long time; indefinitely
例句
We could talk about this until the cows come home, but it won't solve anything.
典故来源
源自乡村生活：放牧的牛群归家时间不定且通常很晚，比喻时间漫长。