Relative clauses — who / whom / whose / which (Unit 94)

Pattern

A relative clause attaches a description to a noun. The pronoun’s job is to stand in for a noun in the relative clause, so the choice depends on what role the pronoun plays, not on the verb tense.

N (antecedent)  +  [who / whom / whose / which / that  +  ...]

The decision rule

Ask three questions in order:

1. Is the antecedent a person or a thing?
   • Person → who / whom / whose (never which for people)
   • Thing → which / that (never who for things)
2. Is the pronoun the subject of the relative clause, or the object?
   • Subject → who (people) / which (things)
   • Object → whom (people) / which (things) — who is acceptable in everyday speech
3. Does the relative clause need a possessive?
   • Yes → whose (works for people and things; whose is the only possessive relative pronoun)

Worked examples

Antecedent	Role in clause	Pronoun	Example
the couple (person)	subject of “got”	who	The couple who got married.
the couple (person)	object of “I thanked”	whom	The couple whom I thanked.
the couple (person)	possessive of “wedding”	whose	The couple whose wedding I attended.
the car (thing)	subject of “broke down”	which	The car which broke down.
the car (thing)	object of “I bought”	which	The car which I bought.
the man (person)	possessive of “car”	whose	The man whose car was stolen.

The common errors

• ❌ The car who broke down. — who is for people, not things.
• ❌ I met a couple to got married. — to is not a relative pronoun.
• ❌ I prefer working to be on my own. — not a relative-clause error, but easy to confuse; in relative clauses, to is the infinitive marker, not a preposition. (See: verb + preposition + -ing.)
• Mixing up object and subject: The man who I saw is acceptable in speech but whom is the formal/correct choice when the pronoun is the object.

that as a universal alternative

that works in place of who or which in defining relative clauses (the kind that identifies which noun you mean), but never for possessive (use whose).

• The man that I saw. ✓
• The man whose car I saw. ✓
• The man that car I saw. ✗

Source

Murphy, English Grammar in Use, Unit 94: Relative clauses 3 (whose / whom / where).