Relative Pronouns!!

relative pronoun	use	example
who	subject or object pronoun for people	I told you about the woman who lives next door.
which	subject or object pronoun for animals and things	Do you see the cat which is lying on the roof?
which	referring to a whole sentence	He couldn’t read which surprised me.
whose	possession for people animals and things	Do you know the boy whose mother is a nurse?
whom	object pronoun for people, especially in non-defining relative clauses (in defining relative clauses we colloquially prefer who)	I was invited by the professor whom I met at the conference.
that	subject or object pronoun for people, animals and things in defining relative clauses (who or which are also possible)	I don’t like the table that stands in the kitchen.

Subject Pronoun or Object Pronoun?

Subject and object pronouns cannot be distinguished by their forms - who, which, that are used for subject and object pronouns. You can, however, distinguish them as follows:

•      If the relative pronoun is followed by a verb, the relative pronoun is a subject pronoun. Subject pronouns must always be used.
•       The apple which is lying on the table
•      If the relative pronoun is not followed by a verb (but by a noun or pronoun), the relative pronoun is an object pronoun. Object pronouns can be dropped in defining relative clauses, which are then called Contact Clauses.
•       The apple (which) George lay on the table
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