The student who won the award is very dedicated.

Relative Pronoun: "who"

The relative pronoun "who" introduces the relative clause that describes "the student." It specifies which student is being talked about (the one who won the award).

The house where I grew up has been renovated.

Relative Pronoun: "where"

The relative pronoun "where" introduces the relative clause that tells us more about the location of the house. It specifies that the house being referred to is the one in which the speaker grew up.

The book which she borrowed was on the top shelf.

Relative Pronoun: "which"

The relative pronoun "which" introduces the relative clause that describes "the book." It specifies which book is being discussed by indicating that it is the one she borrowed.