Russian gives you two ways to attach a "who/which" description to a noun: a participle (прича́стие) — студе́нт, чита́ющий кни́гу ("the student reading a book") — or a кото́рый-clause (a relative clause) — студе́нт, кото́рый чита́ет кни́гу ("the student who is reading a book"). They very often mean exactly the same thing, which is why learners agonise over the choice. The good news is that the decision rests on just two questions: a question of register (who talks like this?) and a question of structure (is a participle even grammatically possible here?). This page answers both, shows you how to convert each into the other in both directions, and pins down the one rule that quietly governs everything: you can only participialize a relative clause when кото́рый is doing a particular job inside it. For the catalogue of the four participle types start at the participles overview; for the relative clause itself see relative clauses with кото́рый.
The two questions
| Question | If a participle... | If кото́рый... |
|---|---|---|
| Register — who says it? | writing, news, formal/academic prose | everything, especially speech (neutral) |
| Structure — is it possible? | only if кото́рый is the SUBJECT or the passivizable direct OBJECT | always possible, any role |
So кото́рый is the safe default: it is always grammatical and always natural. A participle is the optional, bookish upgrade — available only sometimes, and only welcome in written or formal register.
How кото́рый works (the thing being replaced)
Before converting, be clear about кото́рый itself. It agrees in gender and number with the antecedent (the noun it points back to), but it takes its case from its own clause — from the job it does inside the relative clause. This split is the heart of the structural rule.
| Sentence | Role of кото́рый inside its clause | Its case |
|---|---|---|
| студе́нт, кото́рый чита́ет | subject ("he reads") | nominative |
| кни́га, кото́рую я чита́ю | direct object ("I read it") | accusative |
| дом, в кото́ром я живу́ | place ("I live in it") | prepositional |
| друг, с кото́рым я говори́л | companion ("I spoke with him") | instrumental |
Only the first two rows can ever become participles. The bottom two — кото́рый in an oblique, preposition-governed case — are stuck as кото́рый.
Conversion 1: subject кото́рый → active participle
When кото́рый is the subject of its clause (it does the verb's action), it converts to an active participle, which agrees with the antecedent. Present tense → present active participle (-щий); past tense → past active participle (-вший).
| кото́рый-clause (neutral) | Participle (bookish) | English |
|---|---|---|
| студе́нт, кото́рый чита́ет кни́гу | студе́нт, чита́ющий кни́гу | the student who is reading a book |
| лю́ди, кото́рые живу́т здесь | лю́ди, живу́щие здесь | the people who live here |
| тури́сты, кото́рые прие́хали вчера́ | тури́сты, прие́хавшие вчера́ | the tourists who arrived yesterday |
The recipe: take the verb out of the relative clause, replace кото́рый + verb with the matching active participle, and make the participle agree with the antecedent in gender, number, and case (the case the whole noun phrase needs in the main sentence).
Пассажи́ры, ожида́ющие ре́йса в Москву́, прохо́дят к вы́ходу но́мер пять.
Passengers waiting for the flight to Moscow, please proceed to gate five. — present active ожида́ющие (= кото́рые ожида́ют); airport/announcement register suits a participle.
Я говори́л с челове́ком, написа́вшим э́ту статью́.
I spoke with the person who wrote this article. — past active написа́вшим (= кото́рый написа́л); it agrees with челове́ком in the instrumental.
Notice the second example: the participle написа́вшим is in the instrumental because the whole phrase "with the person..." needs the instrumental — that case comes from the main clause, while the form of the participle (active, past) comes from the relative clause. This is the same dual logic as кото́рый, repackaged.
Conversion 2: object кото́рый → passive participle
When кото́рый is the direct object of a transitive verb (the antecedent receives the action), you cannot make an active participle — there is no Russian participle for "the book that I read" in the active. Instead you flip the clause to passive and use a passive participle, which agrees with the antecedent. This is the harder, less intuitive conversion.
| кото́рый-clause (object) | Passive participle (bookish) | English |
|---|---|---|
| письмо́, кото́рое он написа́л | письмо́, напи́санное им | the letter (that) he wrote |
| дом, кото́рый постро́или в 1900 году́ | дом, постро́енный в 1900 году́ | the house (that was) built in 1900 |
| вопро́сы, кото́рые обсужда́ют сейча́с | вопро́сы, обсужда́емые сейча́с | the questions (being) discussed now |
The grammar shifts: the agent "he" (кото́рое он написа́л) becomes the instrumental "им" (напи́санное им), exactly as in a full passive — see the instrumental agent in the wider voice system. Perfective verbs (написа́л) give a past passive participle (напи́санное); imperfective present (обсужда́ют) gives a present passive participle (обсужда́емые), which is especially bookish.
Зако́н, при́нятый в про́шлом году́, вступа́ет в си́лу с января́.
The law passed last year comes into force in January. — past passive при́нятый (= кото́рый при́няли); typical news/legal register.
Кни́га, напи́санная им в мо́лодости, ста́ла кла́ссикой.
The book he wrote in his youth became a classic. — passive напи́санная + instrumental agent им (= кото́рую он написа́л).
The hard limit: oblique кото́рый cannot become a participle
This is the rule that makes participles only sometimes available, and it trips up even advanced learners. If кото́рый sits in a preposition-governed / oblique case — в кото́ром (in which), с кото́рым (with which), о кото́ром (about which), у кото́рого (whose, at whom) — there is no participle that can express it. The relative clause must stay кото́рый.
| кото́рый-clause | Participle? |
|---|---|
| дом, в кото́ром я живу́ ("the house I live in") | impossible — stays кото́рый |
| друг, с кото́рым я учи́лся ("the friend I studied with") | impossible — stays кото́рый |
| фильм, о кото́ром все говоря́т ("the film everyone's talking about") | impossible — stays кото́рый |
Э́то дом, в кото́ром я вы́рос.
This is the house I grew up in. — 'in which' (в кото́ром) is oblique: there is NO participle for it; кото́рый is the only option, in speech and in writing alike.
Колле́га, с кото́рым я рабо́тал над прое́ктом, уе́хал.
The colleague I worked with on the project has left. — 'with whom' (с кото́рым): no participle possible.
So which should learners actually use?
For producing Russian — speaking and most writing — default to кото́рый. It is never wrong, never sounds stiff, and works in every structural position. Active participles in particular sound bookish and even pompous in casual conversation; a кото́рый-clause is what a native speaker says aloud. Reserve participles for deliberately formal writing.
For understanding Russian, you must read participles fluently, because news, literature, and academic prose are saturated with them. The payoff of this page is the ability to mentally unpack any participle back into its кото́рый-clause as you read: see чита́ющий → think "кото́рый чита́ет"; see напи́санный → think "кото́рый написа́ли / кото́рое написа́л". More on the stylistic life of active participles is on using active participles.
В докла́де, подгото́вленном коми́ссией, перечисля́ются все нару́шения.
The report prepared by the commission lists all the violations. — dense written style; mentally unpack to 'кото́рый подгото́вила коми́ссия'.
Common Mistakes
❌ дом, живу́щий я (intending 'the house I live in')
Impossible — 'I live IN it' is oblique (в кото́ром); there is no participle for an oblique-case relative. And a participle never carries its own subject pronoun.
✅ дом, в кото́ром я живу́
the house I live in — oblique кото́рый stays; no participle exists.
❌ кни́га, чита́ющая мной (intending 'the book I'm reading')
Wrong voice — кни́га receives the action, so it can't take an ACTIVE participle. You need a passive participle.
✅ кни́га, чита́емая мной / кни́га, кото́рую я чита́ю
the book I'm reading — passive чита́емая (bookish) or, naturally, the кото́рый-clause.
❌ студе́нт, чита́вшего кни́гу, — мой брат.
Agreement error — as the subject of the main clause the participle must be nominative (чита́вший), agreeing with студе́нт.
✅ студе́нт, чита́вший кни́гу, — мой брат.
the student who was reading a book is my brother — nominative чита́вший agrees with the subject студе́нт.
❌ Э́то па́рень, написа́вший письмо́, кото́рое я люблю́. (casual chat)
Register clash — stacking a participle in everyday speech sounds stilted; a native would use кото́рый throughout.
✅ Э́то па́рень, кото́рый написа́л то письмо́.
That's the guy who wrote that letter. — natural spoken Russian uses кото́рый.
Key Takeaways
- A participle and a кото́рый-clause often mean the same thing but differ on register (participles are bookish; кото́рый is neutral and the only option in speech) and on structure (a participle is only sometimes possible).
- You can convert кото́рый → participle only when кото́рый is the subject (→ active participle: чита́ющий, написа́вший) or the direct object of a transitive verb made passive (→ passive participle: напи́санный, при́нятый).
- Oblique кото́рый with a preposition — в кото́ром, с кото́рым, о кото́ром, у кото́рого — has no participle equivalent; it must stay кото́рый.
- кото́рый agrees in gender/number with the antecedent but takes its case from its own clause; the converted participle agrees with the antecedent in all three (case from the main clause, voice/tense from the original verb).
- Practical advice: produce with кото́рый, read participles fluently. When reading, unpack чита́ющий → кото́рый чита́ет, напи́санный → кото́рый написа́л.
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Start learning Russian→Related Topics
- Participles: OverviewB2 — Russian has four participles (прича́стия) — present active (чита́ющий), past active (чита́вший / прочита́вший), present passive (чита́емый), past passive (прочи́танный) — all of them verbal adjectives that decline and agree with their noun. They are a bookish, written feature; in speech Russians use кото́рый-clauses instead.
- Relative Clauses with КоторыйB1 — Кото́рый ('who/which/that') is the workhorse relative pronoun of Russian. It agrees in GENDER and NUMBER with its antecedent — the noun it points back to — but takes its CASE from its own role inside the relative clause. A comma before кото́рый is obligatory. This page teaches the two-question method that gets the form right every time and shows кото́рый across all six cases.
- Present Active Participles (-ущий/-ащий)B2 — The present active participle (чита́ющий, говоря́щий, иду́щий) turns an imperfective verb into an adjective meaning 'the one who is doing X'. It declines like an adjective and replaces a кото́рый-clause where кото́рый is the subject.
- Past Active Participles (-вший)B2 — The past active participle (чита́вший, прочита́вший, ше́дший) means 'the one who was doing / who did X'. It is formed from the past stem, declines like an adjective, exists in both aspects, and saturates written Russian.
- Passive Participles (-емый, -нный, -тый)B2 — Passive participles describe the receiver of an action: present passive (чита́емый, люби́мый — rare, bookish) and the far more important past passive (прочи́танный, напи́санный, постро́енный, откры́тый), which builds both the adjectival passive and the predicate result construction.
- Using Active Participles in WritingC1 — Active participles (-щий present, -вший past) are a written-register tool that compresses a кото́рый-clause where кото́рый is the SUBJECT: лю́ди, рабо́тающие здесь = кото́рые рабо́тают здесь. They cannot replace кото́рый when it is an object or follows a preposition, and they sound stiff in speech. The key constraints are the subject-only limitation and the comma rule — a participial phrase is set off by commas only when it FOLLOWS the noun.