Declension of interrogative pronouns tko (who) and što (what)
Tko, koga, komu…? Što, čega, čemu…?


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When you think about the concept of grammatical , you probably think about kuća, kuće, kuću, kućom… in other words, you probably think about . And that makes perfect sense, since students of Croatian as a second language usually learn the of nouns (i.e. how to change nouns through cases) first. It’s only later on in the process of learning Croatian that the students also learn that it’s not just the nouns that change in cases: , and some numbers do so, too. So, let’s just drop a bombshell here and say that the interrogative pronouns tko (who) and što (what) change in cases, too, just like any other pronoun. You didn’t see that coming, did you?

Let’s quickly take a look at a few examples to give you a better picture of what I’m talking about: 

Tko ide u Dubrovnik? – Who is going to Dubrovnik? (the nominative case)
Koga ćeš vidjeti ondje? – Whom are you going to see there? (the accusative case)
S kim ideš? – With whom are you going? (the instrumental case)

And also:

Što je to? – What is that? (the nominative case)
Bez čega nikad ne putuješ? – What do you never travel without? (the genitive case)
Čemu se veseliš? – What are you looking forward to? (the dative case)

Can you see it? While it’s easy to see that, for example, kuće, kuću or kućom are just different cases of kuća, it’s not that obvious at first sight to see the connection between tko and koga, or što and čega. But this is exactly what’s going on here: koga is just a different case of tko, and čega is just a different case of što. Mindblown? Don’t worry – you’re not the only one! Students of Croatian as a second language usually learn this thoroughly at the later stages of their process of learning Croatian, when they feel comfortable enough with changing the nouns (and, possibly, adjectives) through cases. 
So – here is how tko and što change through cases:
Declension of interrogative pronouns tko (who) and što (what)
Nominative tko who što what
koga (of) whom čega (of) what
komu (to) whom čemu (to) what
koga whom što what
(na, u…) komu (on, in…) whom (na, u…) čemu (on, in…) what
(s) kim(e) (with) whom (s) čim(e) (with) what

Here’s some more help: When you use tko or što in a particular case, you can also expect the answer in the same case. This means that if a question starts with čega (the genitive case of što), the answer will also be in the genitive case. For example:

Q: Čega se bojiš? – What are you afraid of? (čega – the genitive case of što)
A: Bojim se mraka. – I am afraid of the dark. (mraka – the genitive case of mrak)

That makes sense, doesn’t it? So, before I give you some more examples, you might want to revise your knowledge of what cases (padeži) in the Croatian language are, or rules for each individual case: nominative, genitive, dativeaccusative, vocative, locative, and instrumental.



1 Nominative: Tko je ovo? – Who is this? 
Martin. – Martin.
2 Genitive: Pokraj koga sjediš?  – Next to whom are you sitting?
Pokraj Martina. – Next to Martin.
3 Dative: Komu pišeš poruku? – To whom are you writing a message?
Martinu. – To Martin.
4 Accusative: Koga voliš? – Who(m) do you love?
Martina. – Martin.
5 Vocative:
6 Locative: O komu govoriš? – About whom are you talking?*
O Martinu. – About Martin.
7 Instrumental: S kim živiš? – With whom do you live?
S Martinom. – With Martin.

*Do you think what we think? “Who are you talking about?” sounds more natural than “About whom are you talking?” Yes – I am pretty sure that some of these sentences above in English sound pretty old-fashioned, but that was intentional. Remember when we talked about how there used to be five grammatical cases in Old English? Well, something similar is happening here: although most of “whoms” mentioned above sound obsolete and are replaced by “whos” in contemporary English, I have decided to use the “whoms” here to give you a better picture of what is going on in Croatian – so, tko is who (the subject of a sentence), while all other cases of tko (koga, komu…) are different uses of whom.



1 Nominative: Što je to? – What is that?  
Čokolada. – Chocolate.
2 Genitive: Bez čega ne možeš živjeti? – What can’t you live without?
Bez čokolade. – Without chocolate.
3 Dative: Čemu se veseliš? – What are you looking forward to?
Čokoladi. – To chocolate.
4 Accusative: Što jedeš? – What are you eating?
Čokoladu. – Chocolate.
5 Vocative:
6 Locative: O čemu razgovarate? – What are you talking about?
O čokoladi. – About chocolate.
7 Instrumental: S čime je ovaj kolač? – What is this cake with?
S čokoladom. – With chocolate.
So, the fact that each of these questions determines the case of the answer is the reason why Croatian native speakers usually call them the ‘case questions’, or the ‘helping questions’ (they ‘help’ you determine the right case of, say, a noun).

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‘Case questions’ or ‘helping questions’: what’s that?

If you’ve never had any experience with your Croatian friend or relative (who is not a teacher or a linguist) trying to explain the concept of cases – you can stop reading now, you know what you need to know. But if anyone ever tried to explain cases to you like this: “You know, nominative tko/što, genitive koga/čega, dative komu/čemu…” – and you were (naturally!) left with question marks above your head and a blank look on your face, this might help you find a quantum of sense in that twisted logic!

The thing is that Croats start learning about cases in the 5th grade of primary school, being about 11 years old, and of course, at that point they already speak Croatian really, really well. So, they just have to learn the theory behind the concept that they are already using perfectly well in their everyday life. For Croats, it’s enough just to hear these, as they call them, ‘helping questions’ to be able to determine the case of, say, a noun that comes as an answer. And these ‘helping questions’ are nothing else but the interrogative pronouns tko (who) and što (what) in different cases. As already mentioned above, a particular case of these two ‘helps’ you determine the case of the answer; to the native speakers, the answer comes naturally as something that sounds right. And that’s why Croats also call these questions the ‘case questions’. 

So next time when a Croatian native speaker tries to explain why kuća becomes kuće in “Sjedim ispred kuće.” like this: “Well, kuća is tko/što, so nominative, and kuće is koga/čega, so genitive”… relax – no, I DON’T expect you to understand their explanation! Even though this works as an explanation for Croats, since this is how they learn the concept of cases in school, this is definitely not the best approach to explain how cases work to a non-native speaker. 

Have you ever had an experience of someone trying to explain to you how cases in the Croatian language work using the ‘helping questions’? Or perhaps in some other way? Share your experiences (or traumas? :D) in the comment section below! 

Do you have any other questions about the declension of the interrogative pronouns tko and što? If you want to learn Croatian online and feel the need to discuss this with a Croatian teacher in a live, one-on-one Zoom or Skype session, don’t hesitate to book your free trial lesson here. 

Exercise: Fill the gaps with the correct form of the interrogative pronoun tko or što:

Learning Croatian continues… Next Tuesday we are learning about the most common misconceptions about the Croatian alphabet and pronunciation. If you want us to send you an email with the next Croatian grammar lesson, put your email address here.


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