关于定语从句，专业人士进

是的 定于从句 介词既可以放在从句里也可以前置于先行词前面(当然本身这个介词是与先行词所替代的词相连的 你的例子里 to 就是和person 相连的 也就是you talked to the person)
比如 the factory which he worked in is.....也可以是 the factory in which he worked is....

The person to whom you talked is Mr.Green
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The person whom you talked to is Mr.Green

to可提前

The person to whom you talked is Mr.Green.
=The person whom you talked to is Mr.Green

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