I am the only student who can run faster than Peter.the only 修饰先行词,为什么用 who 不用 that?

题目

I am the only student who can run faster than Peter.the only 修饰先行词,为什么用 who 不用 that?

答案

先行词指人时,关系代词在从句中作主语时,只能用who作引导词的定语从句.
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