a hard nut to crack
US /ə hɑrd nʌt tu kræk/
UK /ə hɑːd nʌt tu kræk/
成語
一個難題, 一個難纏的人
a problem that is difficult to solve or a person who is difficult to understand or deal with
範例:
•
This math problem is really a hard nut to crack.
這個數學問題真是一個難題。
•
My boss is a hard nut to crack; he rarely changes his mind.
我的老闆真是個難纏的人；他很少改變主意。