Can who be used as a preposition?

"Who" is a pronoun, not a preposition. Prepositions are words that show the relationship between a noun or pronoun and another word in the sentence.

Here are some examples of prepositions:

* on the table

* in the box

* with my friend

* under the bed

"Who" is used to ask questions or to refer to people. For example:

* Who is coming to the party?

* The person who called is my friend.

You can't use "who" as a preposition. If you want to express a relationship between a person and something else, you'll need to use a different preposition.

For example, instead of saying "who is the book for?", you would say "for whom is the book?"