a tough nut的用法和样例：
例句
- I asked her for the money, but she was a tough nut to crack and I went away without it.
我向她要钱，但她这个人很难对付，因此我空手而归。 - The final exam was a tough nut.
毕业考试不好对付。 - She's a tough nut to crack; I don't think she'll give us permission.
她这个人不好说话，我想她不会答应我们的。
词汇搭配
- a tough nut to crack 难对付的人
