Kies asks or relates a possessor: Kies telefono sonoras? “Whose phone is ringing?” and la gasto, kies telefono sonoras “the guest whose phone is ringing.” It is invariant: it never takes plural -j or accusative -n, even when the possessed noun is plural or is a direct object.
The possession uses on this page are neutral in conversation and writing. More abstract uses with action nouns are especially common in formal and academic prose, where kies may identify the semantic agent or object of an action.
Kies in the 5×9 table
Esperanto’s table words combine five fixed initial series with nine fixed semantic domains. Ki- gives question or relative force; -es gives the possessor domain.
| Dimension | Relevant forms |
|---|---|
| Initial series | ki- question/relative, ti- demonstrative, i- indefinite, ĉi- universal, neni- negative |
| Final domains | -u individual, -o thing, -a kind, -es possessor, -e place, -am time, -al reason, -el manner, -om quantity |
| The -es column | kies, ties, ies, ĉies, nenies |
| The ki- row | kiu, kio, kia, kies, kie, kiam, kial, kiel, kiom |
The final sequence -es is a fixed table-word ending, not an ordinary case suffix. Forms such as kiesa, kiesn, and kiesj do not belong to the standard system.
See Case and Number on Correlatives for a comparison of which table-word endings license -j and -n.
Direct questions about possession
Kies normally stands before the possessed noun, where it acts as a determiner. Do not add la.
Kies telefono sonoras en la kuirejo?
Whose phone is ringing in the kitchen?
Kies mantelon vi prenis erare?
Whose coat did you take by mistake?
— Kies estas ĉi tiuj valizoj? — Ili apartenas al la franca grupo.
— Whose are these suitcases? — They belong to the French group.
In the second sentence, mantelon takes accusative -n because it is the object of prenis. Kies stays unchanged. In the exchange, kies stands predicatively because the possessed item is already named by ĉi tiuj valizoj.
Kies infanoj ludas antaŭ la domo?
Whose children are playing in front of the house?
The plural belongs to infanoj, not to kies. The possessor itself may be one person or several; kies does not encode that number.
Embedded questions
The same word introduces an indirect question about possession.
Mi ne memoras, kies ideo estis la nokta ekskurso.
I don't remember whose idea the night excursion was.
Ĉu vi scias, kies aŭton la polico forportis?
Do you know whose car the police towed away?
The entire phrases kies ideo and kies aŭton belong inside the embedded clauses. As with direct questions, kies normally begins the question phrase even when that phrase is an object.
English often leaves whose ambiguous between asking about a possessor and asking “who has.” Esperanto keeps these structures separate:
Kies estas la rezerva ŝlosilo? Kiu havas ĝin nun?
Whose is the spare key? Who has it now?
Ownership and current possession are different questions.
Relative kies
Relative kies links an antecedent to something belonging or closely related to it. The antecedent can be a person, animal, organization, object, or other entity.
Mi renkontis la najbarinon, kies filo laboras en la biblioteko.
I met the neighbor whose son works at the library.
La firmao, kies produktojn ni testis, malfermos oficejon ĉi tie.
The company whose products we tested will open an office here.
In the first relative clause, the neighbor is the possessor of filo. In the second, the company is related as possessor or producer of produktojn. Kies itself does not agree with feminine najbarinon, singular firmao, or plural produktojn.
The possessed noun has its own role inside the relative clause:
Jen la verkisto, kies romanon mi finis hieraŭ.
Here is the writer whose novel I finished yesterday.
Romanon is the object of finis, so it takes -n. The antecedent verkisto is outside that clause role; it merely supplies the possessor represented by kies.
Possession, semantic agent, and semantic object
Normative kies covers three related uses of de: possession/belonging, the semantic subject of an action noun, and the semantic object of an action noun.
Ni honoris la esploristinon, kies malkovro ŝanĝis la traktadon.
We honored the researcher whose discovery changed the treatment.
The researcher is the semantic agent of malkovro: she discovered something.
La propono, pri kies akcepto ni voĉdonos morgaŭ, restas polemika.
The proposal whose acceptance we will vote on tomorrow remains controversial.
The proposal is the semantic object of akcepto: someone may accept the proposal. This second pattern is grammatical but structurally denser and is most at home in formal writing. In everyday speech, la propono, pri la akcepto de kiu... or a finite-clause rewrite may be easier to process.
Kies versus de kiu
Kies does not replace every possible de kiu. It covers possessive/relational de, but de also marks source, separation, origin, and passive agents.
Kies letero estas sur la tablo?
Whose letter is on the table?
De kiu vi ricevis la leteron?
Who did you receive the letter from?
The first asks whose letter it is; the second asks its source in the act of receiving. Translating English whose/from whom mechanically would erase that distinction.
In relative clauses, use de kiu when the underlying relation truly requires de as a verbal preposition:
La kolego, de kiu mi ricevis la dosieron, laboras en Bruselo.
The colleague from whom I received the file works in Brussels.
Also use el kiu/kiuj for selection from a group; kies never means “one of whom.”
Venis tri kandidatoj, el kiuj du jam laboris kun ni.
Three candidates came, two of whom had already worked with us.
De kies can still be correct
Sometimes a separate preposition governs the entire noun phrase beginning with kies:
La serpento, de kies mordo la hundo mortis, malaperis en la herbo.
The snake from whose bite the dog died disappeared into the grass.
Here kies determines mordo (“the snake’s bite”), while the outer de marks the cause/source relationship of morti de la mordo. This is not redundant de + kies; the two elements operate at different structural levels.
Common Mistakes
1. Adding case to kies
❌ Kiesn biciklon vi pruntis?
Incorrect — kies never takes accusative -n.
✅ Kies biciklon vi pruntis?
Whose bicycle did you borrow?
2. Making kies agree with a plural noun
❌ Kiesj dokumentoj mankas?
Incorrect — plural marking belongs on dokumentoj.
✅ Kies dokumentoj mankas?
Whose documents are missing?
3. Adding la before kies
❌ La kies sako restis en la trajno?
Incorrect — kies already determines sako.
✅ Kies sako restis en la trajno?
Whose bag was left on the train?
4. Using kies for source
❌ Kies vi ricevis ĉi tiun mesaĝon?
Incorrect — the question asks about source, not a possessed noun.
✅ De kiu vi ricevis ĉi tiun mesaĝon?
Who did you receive this message from?
5. Using kies for one member of a group
❌ Ni intervjuis kvin kandidatojn, kies du loĝas proksime.
Incorrect — the meaning is two out of the five.
✅ Ni intervjuis kvin kandidatojn, el kiuj du loĝas proksime.
We interviewed five candidates, two of whom live nearby.
Key Takeaways
- Ki- supplies question/relative force; -es supplies the possessor relation.
- Kies is invariant: never add -j or -n.
- Put kies before its noun without la; case and number appear on the possessed phrase.
- Relative kies can express possession, the agent of an action noun, or its semantic object.
- Keep de kiu, el kiu, al kiu, and other prepositional forms when the relation is not possessive in the relevant sense.
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Start learning Esperanto →Related Topics
- Kiu: The Question/Relative Individual CorrelativeA1 — Use kiu to ask or relate which individual, adding -j for plural individuals and -n when its role requires the accusative.
- Ties: The Demonstrative Possessor CorrelativeA2 — Use ties to point to the possessor associated with a demonstrated person or thing, without agreement or an article.
- The Table-Word SystemA1 — Learn Esperanto's 45 table words as a five-by-nine meaning system for questions, demonstrations, indefinites, universals, and negatives.
- Case and Number on CorrelativesA2 — Learn exactly which correlative families accept plural -j, object -n, or directional -n, and which remain invariant.
- Kies in Relative ClausesB1 — Use kies to connect a person or thing with something belonging to it, including the subject or object behind an action noun.
- De-Phrases versus PossessivesB1 — Choose between compact possessive forms such as mia and fuller de-phrases, and avoid ambiguity about ownership, source, and authorship.