for the life of you
US /fɔr ðə laɪf əv ju/
UK /fɔr ðə laɪf əv ju/
1.
怎么也, 无论如何
even with the greatest effort; used to emphasize that someone cannot do something
:
•
I can't remember his name for the life of me.
我怎么也想不起他的名字。
•
She couldn't understand why he did it for the life of her.
她怎么也不明白他为什么这样做。