I am a beginner and I can't understand the difference between "kio" and "kiu". The explanations that I have read so far only leaves me confused and to me it seems that "kio" and "kiu" are sometimes interchangeable.

3 Answers 3


kio = what


Kio estas tio? → What is that? (Is it a dog? Is it a cat?)

Kion vi deziras? → What do you want? (A pen? An ice-cream?)

kiu = which [one of a group, type, etc.] or who


Kiu estas via aŭto? → Which is your car? (Which one of all these cars is yours? That one over there? Or this one here?)

Kiun vi deziras? → Which do you want? (Which thing of all these things do you want? The pen? Or maybe the ice-cream?)

Kiu manĝis mian glaciaĵon? → Who ate my ice-cream? (To match the meaning of “which” you can think of who meaning which one of the people.)

Compare Kion vi volas? and Kiun vi volas? above to see the difference directly.

  • A slight detail - "voli" is for verbs, and "deziri" is for nouns. You might want to use "kion vi deziras" instead. Commented Sep 7, 2016 at 15:26
  • 3
    @ClaytonRamsey "voli" is actually very commonly used with nouns, and "deziri" can be used with verbs; ReVo says the difference between "voli" and "deziri" is that "voli" often implies an intention of acting to realize the desire.
    – kristan
    Commented Sep 7, 2016 at 18:12

They are definitely not interchangable.

Trying to literally translate them to English you would end up in

kio = what

kiu = which

A rule that I find quite useful is

If it stands with a nounish word, it's "kiu", if it stands independently it's "kio".


Kio estas en la skatolo kaj kio estas sur la tablo?

En la skatolo estas skribiloj kaj sur la tablo estas unu skribilo.

As opposed to

Kiuj skribiloj estas en la skatolo kaj kiu skribilo estas sur la tablo?

In the first example "kio" stands indipendently and in the second example it stands together with the noun "skribilo(j)". According to the form of the noun, "kiu" also takes the plural and accusative markers.

What is sometimes confusing is, that you'd drop the noun that stands with "kiu". For example again the above dialog

Kio estas en la skatolo kaj kio estas sur la tablo?

En la skatolo estas skribiloj kaj sur la tablo estas unu skribilo.

Kiuj estas en la skatolo kaj kiu estas sur la tablo?

The answer to the first question made it clear, that we are talking about several pens in the box and one pen on the table. So in the followup question we can drop the noun, because we can assume it out of the context.

So in order to "kiu" to be able to stand alone there has to be a clear context, which noun it is refering to. If there's no such context it is usually assumed that one is talking about a person.

Kio alvenis? (What has just arrived)


Kiu sidas en la aŭto? (Who is sitting in the car?)

Mia patro kaj lia hundo.

If you ask

Kio sidas en la aŭto?

a possible answer would be

Persono kaj hundo.

Kiu hundo sidas en la aŭto? (Which dog ...)

Tiu de mia patro. (My father's one)

The corresponding -io and -iu words behave similarly.


Tiu goes with a noun, tiu homo: that person, for example; tio does not. The slightly complicated thing is that for tiu the noun might be implied, so, gesturing at a room of people including someone standing on their head: rigardu tiun is correct, since the homo in rigardu tiun homon is understood, but gesturing at an explosion rigardu tion is correct.

Once tiu and tio make sense, kiu and kio follow; kiu is which one, so it asks which among a collection of objects is meant, whereas kio means what.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.