Relative Clauses with Который

To say "the man who called", "the book that I'm reading", or "the house in which I live", Russian uses one highly productive relative pronoun: кото́рый. It is the main connector for building complex sentences, and it has exactly one tricky feature — it is pulled in two directions at once. Its gender and number are decided by the noun it refers back to (the antecedent), but its case is decided by what job it does inside its own clause. Once you separate those two questions, кото́рый becomes mechanical. This page also pairs naturally with the interrogative uses of чей, како́й, кото́рый.

The core rule: agreement up, case in

A relative clause is a mini-sentence stuck onto a noun to describe it. The pronoun кото́рый is the hinge. Its form is computed from two independent sources:

1. Gender and number → copied from the antecedent (the noun in the main clause that кото́рый replaces). Masculine antecedent → masculine кото́рый; plural antecedent → plural кото́рые.
2. Case → determined by кото́рый's own grammatical role inside the relative clause — subject, direct object, object of a preposition, and so on.

So a single antecedent can produce кото́рый in any of the six cases, depending on what the relative clause does with it.

Same antecedent (челове́к), two different cases (кото́рый vs кото́рого), because the relative clause uses the man differently — once as the one doing the calling, once as the one being seen.

The two-question method, worked through

Whenever you build a relative clause, ask these two questions in order:

Question 1 — what is the antecedent? Find the noun being described. Its gender and number fix the root of кото́рый.

Question 2 — what role does кото́рый play in its own clause? Mentally rebuild the relative clause as a standalone sentence with кото́рый in place. Whatever case that role demands is the case of кото́рый.

Worked example: "the book that I'm reading."

• Q1: antecedent = кни́га, feminine singular → кото́рая family.
• Q2: inside the clause, кни́га is the direct object of чита́ю ("I'm reading the book") → accusative → feminine accusative = кото́рую.

Worked example: "the house in which I live."

• Q1: antecedent = дом, masculine singular → кото́рый family.
• Q2: inside the clause, the role is в
  • location ("I live in the house") → preposition в governs the prepositional → masculine prepositional = кото́ром, and the preposition sits right in front: в кото́ром.

Note where the preposition goes: in Russian the preposition stays glued to кото́рый inside the clause (в кото́ром, с кото́рым). English can strand it at the end ("the house I live in"), but Russian never does.

Который across the cases

Here is the same logic applied to every case, each driven by a different role in the relative clause:

For animate masculine antecedents in the accusative, remember the animacy rule: the accusative copies the genitive, so "the man I saw" is кото́рого, not кото́рый.

The comma is obligatory

Russian punctuation is grammatical, not stylistic. Every relative clause introduced by кото́рый is set off by a comma (and a closing comma if the clause is embedded in the middle of the sentence). There is no Russian equivalent of the English "that"-clause that drops the comma — кото́рый always gets one.

How this differs from English

English has a scattered, partly invariable system: who (for people), which (for things), that, whose, whom — and it freely drops the pronoun ("the book I read") and strands prepositions ("the friend I talked to"). Russian replaces all of that with one declinable word, кото́рый, and bans both shortcuts. Three concrete contrasts trip up English speakers: (1) Russian cannot drop кото́рый — there is no "the book Ø I read"; (2) Russian cannot strand the preposition — it must sit before кото́рый (с кото́рым, not кото́рым…с); (3) Russian does not care whether the antecedent is a person or a thing — кото́рый covers who, which, and that alike.

Common Mistakes

Key Takeaways

• кото́рый is the all-purpose relative pronoun: who / which / that, for people and things alike.
• It agrees in gender and number with the antecedent (look left) but takes its case from its role inside the relative clause (look right) — two independent decisions.
• Use the two-question method: (1) what is the antecedent? → gender/number; (2) what role does it play in its own clause? → case.
• A comma before кото́рый is obligatory, with a closing comma if the clause is embedded.
• Russian never drops кото́рый and never strands the preposition — it sits before кото́рый (в кото́ром, с кото́рым).
• For animate masculine accusative, the animacy rule gives кото́рого, not кото́рый.