She's the only one who's studying Frence?为什么用who,而不用that?

问题描述:

She's the only one who's studying Frence?为什么用who,而不用that?
不是说定语从句中有only修饰时,关系词用that么?

先行词为指人的all,one,ones,someone,anyone,everyone,no one等代词时,用who.先行词被the only, the very,the last, the just, the same 等修饰时,用that。 那么这个句子的先行词又是指人one 又是被the only修饰,这不是矛盾么?你所看到的是先行词指事物时,先行词被the only, the very,the last, the just, the same 等修饰时,用that。