定语从句VS地点状语从句

You'd better make a mark where you have any questions.
You'd better make a mark at the place where you have anyquestions.
以上两句字意思相同，但第一个是状语从句，后一个是定语从句。定语从句有先行词THE PLACE，而状语从句没有。

状语从句中where引导的句子做地点状语，不出现place
定语从句出现先行词place，再用where引导的定语来修饰place