To touch a raw nerve 触及痛处

当我们在看牙医时，如果医生碰到了暴露在外的神经 “a raw nerve”，那么我们会感到剧烈的疼痛。而表达 “to touch a (raw) nerve” 的意思则是 “因谈到了敏感的话题而让人感到难过”，也就是我们平常说的 “触及到了某人的痛处”。

例句

I could tell I'd touched a nerve when I asked Chen about her mother.
当我问及小陈她妈妈的时候，看得出来我触及到了她的痛处。

The article I wrote on exercising seems to have touched a nerve with the readers. We've been getting lots of complaints.
我写的那篇有关锻炼的文章似乎触到了读者们的痛处。我们陆续收到了很多投诉。

Don't worry! I know you didn't mean to upset Clare. I think you just touched a nerve when you commented on her cooking.
别担心！我知道你当时并不是故意要让克莱尔生气的。我觉得你只是在评论她的厨艺时戳到了她的痛处而已。