Relative Pronouns in Czech

In Brief

The everyday Czech equivalent of English “who,” “which,” or “that” is usually který, with the forms který, která, které. Its gender and number match the noun it describes, but its case—the ending that marks its job in the sentence—comes from the relative clause itself: žena, kterou znám (“the woman I know”), but žena, která mě zná (“the woman who knows me”). Unlike English, standard Czech does not normally leave this pronoun out.

Overview

A relative clause is a part of a sentence that identifies or describes a noun: “the neighbour who lives upstairs” or “the book that I bought.” A relative pronoun links that clause to the noun. Czech most often uses a form of který for this purpose, whether the noun is a person or a thing.

Relative pronouns become a central topic around B1 because they bring together several earlier skills. You need to recognise a noun’s gender and number, and you need to see what job the pronoun has inside its own clause. That job determines its case: it might be the subject (the person or thing doing the action), the direct object (the person or thing directly affected), or the complement of a preposition such as o (“about”) or s (“with”).

English gives limited help here. It can use “who,” “which,” or “that,” and it can omit an object pronoun entirely: “the film we saw.” Czech normally states the link and marks its grammatical role: film, který jsme viděli. Once you learn to analyse the smaller clause by itself, the endings become much more predictable.

How It Works

Start with the clause, not the English word

The key pattern is:

noun + comma + relative pronoun + relative clause

For example:

• Znám ženu. Ta žena pracuje v bance. → Znám ženu, která pracuje v bance. — “I know a woman who works in a bank.”
• Znám ženu. Vidíš tu ženu. → Znám ženu, kterou vidíš. — “I know the woman you see.”

In both combined sentences, the pronoun refers to žena, so it is feminine singular. In the first relative clause, the woman performs the action, so která is nominative. In the second, you see the woman, so kterou is accusative.

A reliable two-step method is:

1. Find the antecedent (the noun the relative pronoun points back to). Its gender and number determine which column of forms you need.
2. Temporarily treat the relative clause as a separate sentence. The verb or preposition in that clause determines the pronoun’s case.

The case of the antecedent in the main clause does not control the pronoun’s case. Compare:

• Mluvím se ženou, která bydlí vedle. — “I am talking to a woman who lives next door.”
• Mluvím se ženou, kterou znáš. — “I am talking to a woman whom you know.”

The main-clause noun is instrumental in both sentences (se ženou), but the relative pronoun is nominative in the first clause and accusative in the second.

Declension of který

Který declines like a hard adjective. The table omits the vocative, the case used for direct address, because a relative pronoun does not normally address anyone.

Case and usual role	Masculine animate singular	Masculine inanimate singular	Feminine singular	Neuter singular	Masculine animate plural	Masculine inanimate / feminine plural	Neuter plural
Nominative: subject	který	který	která	které	kteří	které	která
Genitive: possession; after certain prepositions	kterého	kterého	které	kterého	kterých	kterých	kterých
Dative: recipient or beneficiary	kterému	kterému	které	kterému	kterým	kterým	kterým
Accusative: direct object; after certain prepositions	kterého	který	kterou	které	které	které	která
Locative: after prepositions such as o, v, na	kterém	kterém	které	kterém	kterých	kterých	kterých
Instrumental: means or companion; after s	kterým	kterým	kterou	kterým	kterými	kterými	kterými

“Masculine animate” mainly covers male people and animals, while “masculine inanimate” covers objects and abstract nouns. The distinction is especially visible in the accusative singular: muž, kterého znám (“the man I know”), but film, který znám (“the film I know”).

The nominative plural also deserves attention:

• studenti, kteří studují češtinu — male or mixed-gender students who study Czech
• ženy, které tu pracují — women who work here
• domy, které stojí u řeky — houses that stand by the river
• města, která leží na Moravě — towns that lie in Moravia

Subject, object, or recipient?

Do not ask only what the antecedent does in the whole sentence. Ask what the relative pronoun does after the comma.

• lékař, který mi pomohl — “the doctor who helped me.” The doctor is the subject, so use nominative.
• lékař, kterého jsem navštívil — “the doctor whom I visited.” I visited the doctor, so use accusative.
• lékař, kterému jsem zavolal — “the doctor whom I called.” Zavolat někomu takes the dative, so use kterému.

This is also why translating “whom” mechanically does not work. English “whom” may correspond to accusative, dative, genitive, or a prepositional form in Czech.

Keep the preposition with the pronoun

If the Czech verb or expression requires a preposition, place it directly before the relative pronoun. Unlike conversational English, Czech cannot strand that preposition at the end of the clause.

Czech pattern	Natural English equivalent	Required case
dům, ve kterém bydlím	the house I live in	locative after v/ve
téma, o kterém mluvíme	the topic we are talking about	locative after o
kolega, se kterým pracuji	the colleague I work with	instrumental after s/se
firma, pro kterou pracuji	the company I work for	accusative after pro
restaurace, do které chodíme	the restaurant we go to	genitive after do
člověk, ke kterému jdu	the person I am going to see	dative after k/ke

The longer forms ve, se, and ke are chosen where Czech pronunciation requires or favours them; the case rule remains the same.

Czech commas are not optional here

Czech separates a relative clause from the main clause with a comma. This applies even where English has no comma because the information identifies exactly which person or thing is meant:

• Hledám knihu, kterou jsi mi doporučil. — “I’m looking for the book you recommended to me.”
• Moje sestra, která žije v Brně, přijede zítra. — “My sister, who lives in Brno, will arrive tomorrow.”

If the relative clause interrupts the main clause, put a comma at both ends: Kniha, kterou právě čtu, je výborná. English punctuation distinguishes more strongly between identifying and extra information; do not transfer that distinction directly to Czech.

Co after to, všechno, něco, and nic

The unchanging word co is standard in useful patterns where the antecedent has a broad meaning rather than naming an ordinary person or object:

• To, co říkáš, je pravda. — “What you are saying is true.”
• Všechno, co potřebujeme, už máme. — “We already have everything we need.”
• Nenašel jsem nic, co by mi pomohlo. — “I found nothing that would help me.”

Because co does not decline, another relative form is needed when a preposition must express the relationship. Compare to, co čtu (“what I am reading”) with to, o čem čtu (“what I am reading about”) and to, s čím pracuji (“what I am working with”). The forms čem and čím belong to the declension of co used after prepositions.

After an ordinary noun, co is also very common in informal speech: ten kluk, co tu pracuje (“the guy who works here”). Neutral and formal writing usually prefers který: ten muž, který tu pracuje.

Examples in Context

Czech	English	Note
Žena, kterou znám, pracuje v knihovně.	The woman I know works in a library.	Feminine accusative: I know her.
Žena, která mě zná, pracuje v knihovně.	The woman who knows me works in a library.	Feminine nominative: she knows me.
Dům, ve kterém bydlím, patří mým rodičům.	The house I live in belongs to my parents.	v/ve + locative
Film, který jsme včera viděli, byl dlouhý.	The film we saw yesterday was long.	Masculine inanimate accusative
Lidé, kteří přišli první, už sedí uvnitř.	The people who arrived first are already sitting inside.	Masculine animate nominative plural
Města, která jsme navštívili, byla velmi klidná.	The towns we visited were very quiet.	Neuter accusative plural
To je kolegyně, které každý týden píšu.	This is the colleague I write to every week.	Feminine dative after psát někomu
Nemůžu najít klíč, kterým se otevírá sklep.	I can’t find the key that opens the cellar.	Instrumental: the key is the means used.
Znáš kavárnu, do které chodí Jana?	Do you know the café Jana goes to?	do + genitive
To je otázka, na kterou neumím odpovědět.	That is a question I cannot answer.	odpovědět na + accusative
Soused, se kterým jsem mluvil, je architekt.	The neighbour I spoke with is an architect.	s/se + instrumental
Všechno, co potřebuji, mám v batohu.	I have everything I need in my backpack.	Standard co after všechno
To, o čem mluvíš, se stalo minulý týden.	What you are talking about happened last week.	Preposition o requires čem.
Ten pán, co čeká venku, je můj učitel.	The man waiting outside is my teacher.	Common colloquial co
Kniha, kterou mi půjčila Eva, se mi moc líbí.	I really like the book Eva lent me.	The full relative clause is enclosed by commas.

Common Mistakes

Using the nominative as a default

• Wrong: To je muž, který jsem včera potkal.
• Right: To je muž, kterého jsem včera potkal.
• Why: In the relative clause, “I met the man,” the man is the direct object. Masculine animate accusative is kterého.

Copying the antecedent’s case

• Wrong: Mluvím se studentkou, kterou bydlí vedle.
• Right: Mluvím se studentkou, která bydlí vedle.
• Why: Studentkou is instrumental because of s in the main clause. Inside the relative clause, however, the student is the subject of bydlí, so the pronoun is nominative která.

Omitting a pronoun as English does

• Wrong: To je telefon, jsem koupil včera.
• Right: To je telefon, který jsem koupil včera.
• Why: English allows “the phone I bought,” but standard Czech needs an expressed relative link.

Dropping or stranding the preposition

• Wrong: To je firma, kterou pracuji.
• Right: To je firma, pro kterou pracuji.
• Why: Czech says pracovat pro firmu. The preposition stays before the pronoun; it cannot be left at the end as in English “the company I work for.”

Mixing up plural gender forms

• Wrong: Lidé, které tam pracují, jsou milí.
• Right: Lidé, kteří tam pracují, jsou milí.
• Why: Lidé is masculine animate plural, and the pronoun is the subject, so the required nominative form is kteří. By contrast, use města, která for neuter plural.

Using colloquial co everywhere

• Too informal for careful writing: Zaměstnanci, co pracují o víkendu, dostanou volno.
• Neutral standard: Zaměstnanci, kteří pracují o víkendu, dostanou volno.
• Why: Relative co after an ordinary noun is widespread in conversation, but který is the safer choice in an exam, report, formal email, or edited text.

Usage Notes

Který covers people and things

Czech does not make the same basic split as English “who” for people and “which” for things. Který can refer to either: člověk, kterého znám and program, který používám. Its forms carry information about gender, number, and case rather than a person-versus-thing distinction.

The same word also functions as the question word “which”: Který vlak jede do Brna? (“Which train goes to Brno?”). A question has no antecedent before it; a relative use points back to a noun and introduces a clause. Context and punctuation make the function clear.

Co can be standard or colloquial

In všechno, co vím and to, co potřebuješ, co is not merely casual shorthand; it is the normal standard choice. In soused, co bydlí nahoře, it is conversational. This distinction is more useful than the oversimplified rule that co is always “incorrect.”

In very informal constructions, speakers may use co and then repeat its role with a small pronoun, for example člověk, co jsem ho včera viděl (“the person I saw yesterday”). You should recognise this in speech, but learners are better served by the cleaner standard form člověk, kterého jsem včera viděl.

Place the clause next to what it describes

Czech word order is flexible, but a relative clause should normally follow its antecedent closely. Otherwise, the sentence may briefly suggest the wrong connection. Instead of crowding several nouns before the clause, reorganise the sentence so that the intended noun stands immediately before the comma and pronoun.

Relative clauses and agreement are separate issues

The form of který follows the antecedent’s gender and number, but a past-tense verb or adjective inside the clause follows its own subject. In žena, kterou jsme viděli (“the woman we saw”), kterou is feminine because it refers to žena, while viděli is plural because the unspoken subject is “we.” Do not expect every ending in the clause to match the antecedent.

Beyond the Basics / Advanced Use

Jenž in formal and literary Czech

Jenž is a more formal relative pronoun meaning “who” or “which.” It appears in literature, journalism, official language, and deliberately elevated prose. Forms you may encounter include jenž, jež, jehož, jíž, jemuž, jimž, and prepositional forms such as o němž or s níž.

Compare projekt, o kterém jsme mluvili with the more formal projekt, o němž jsme mluvili. In ordinary conversation, který is much easier and more natural. At B1, recognition of common jenž forms matters more than active command of its full declension.

Possessive relatives: jehož, jejíž, jejichž

Written Czech can express “whose” compactly:

• autor, jehož knihu čtu — “the author whose book I am reading”
• firma, jejíž výrobky známe — “the company whose products we know”
• studenti, jejichž práce byly vybrány — “the students whose work was selected”

The choice reflects the antecedent: jehož for a masculine or neuter singular antecedent, jejíž for feminine singular, and jejichž for plural. These forms are fixed for the possessed item: in autor, jehož knihu čtu, jehož refers back to the male author even though knihu is feminine accusative. Spoken Czech often rephrases to avoid this formal pattern.

Kdo, co, kde, and kdy as relative words

Not every Czech relative clause begins with který. Several paired patterns are extremely common:

• ten, kdo pomůže — “the one who helps”
• to, co potřebujeme — “what we need”
• tam, kde jsme se potkali — “where we met”
• den, kdy jsme přijeli — “the day when we arrived”

After a specific noun, Czech may offer more than one natural structure. Místo, kde bydlím (“the place where I live”) focuses on location, while dům, ve kterém bydlím (“the house I live in”) uses a declined pronoun after a preposition. Learning these as whole patterns is often more efficient than forcing every English “where” or “when” into a form of který.

Relative clauses with the conditional

A relative clause can contain by, especially after negative or broad antecedents when English uses “would” or “could”:

• Hledám někoho, kdo by mi mohl poradit. — “I’m looking for someone who could advise me.”
• Není nic, co bych chtěl změnit. — “There is nothing I would like to change.”

Here, the choice of relative word and the conditional are separate decisions. The relative word still gets its role from the clause; by adds possibility, preference, or a non-specific meaning.

Practice Tips

1. Expand two short sentences into one. Start with Vidím muže. Muž čeká. and build Vidím muže, který čeká. Then change the second sentence to Znáš muže and build Vidím muže, kterého znáš. This makes case selection visible.
2. Make a six-case chain with one noun. Try kolega, který…; kolega, bez kterého…; kolega, kterému…; kolega, kterého…; kolega, o kterém…; kolega, se kterým…. Add a natural clause to each form rather than memorising endings in isolation.
3. Listen for the word before the pronoun. When you hear o kterém, pro kterou, or se kterými, note the preposition and predict the case. When you hear co, ask whether it follows to/všechno/něco/nic or whether it is an informal replacement after an ordinary noun.

Related Concepts

• Prerequisite: Subordinate Clauses — relative clauses are subordinate clauses, so the same basic clause boundaries and comma rules apply.