如果你想询问为什么某人不说话了，你可以问："Why aren't you talking?" 或者 "What's wrong? Why have you stopped talking?" 这个短语来自英语中的动词"to talk"，表示"说话"的意思，加上"not"就变成了否定形式，表示"没有说话"。例句：

Why aren't you talking? You were just saying something a minute ago.

What's wrong? Why have you stopped talking? You're usually so chatty.

I noticed you weren't talking much at the party last night. Is everything okay?

I tried to strike up a conversation with her, but she wasn't talking much. She seemed a bit distant.