at one's wit's end(98上~week17)

(1)idiom/phrase:at one’s wit’s end
(2)meaning: at the limits of one's mental resources. (想不出辦法，黔驢技窮)
(3)example:
I'm at my wit's end with this problem. I cannot figure it out.


備註: one’s可以替換成my, your, his, her---某某人的。