carry a torch for somebody

单相思
A:John hasn't got married up to now.
A:约翰到现在还没结婚呢。
B:Don't you know that he has been carrying a torch for Mary for years?
B：难道你不知道他这么多年来一直单恋着玛丽吗?
A:Really? Does Mary know that?
A:真的?玛丽知道吗?
B:Of course not.
B:当然不知道。
A:How silly John is!
A:约翰太傻了!