Learn Hardcore Croatian: On želi upisati tečaj hrvatskog jezika. - He wants to enroll in a Croatian language course.

you want to make the subject very clear (for example, to contrast with someone else: On želi, ali ona ne želi. – He wants to, but she doesn’t.), or
the context is not clear and you need to say it’s he, not she or it.

So in everyday speech, Želi upisati tečaj hrvatskog jezika. is perfectly natural if it’s already clear who you are talking about.

What exactly does želi mean, and what verb does it come from?

Želi is the 3rd person singular present tense of the verb željeti (to want, to wish).

Present tense of željeti:

ja želim – I want
ti želiš – you want (sg.)
on/ona/ono želi – he/she/it wants
mi želimo – we want
vi želite – you want (pl./formal)
oni/one/ona žele – they want

Nuance:

željeti is often slightly softer or more polite, closer to wish/would like.
Another very common verb is htjeti (to want), whose 3rd person form is hoće. It can sound a bit more direct or strong, especially in some contexts.

In this sentence On želi upisati tečaj hrvatskog jezika, želi is best understood simply as wants or wants to.

Why is upisati in the infinitive? Could I say On želi da upiše tečaj hrvatskog jezika?

In standard Croatian, verbs of wanting, needing, planning, starting, etc. very often take an infinitive:

On želi upisati tečaj. – He wants to enroll in the course.
Mora upisati tečaj. – He has to enroll in the course.
Planira upisati tečaj. – He plans to enroll in the course.

So On želi upisati tečaj hrvatskog jezika. is the standard and most natural pattern.

The structure želi da upiše tečaj:

is much more typical for Serbian,
in Croatian it is heard in colloquial speech (especially in some regions),
but in standard Croatian it is generally avoided and often felt as non‑standard or “Serbian‑sounding”.

So for good Croatian, stick with the infinitive:

On želi upisati tečaj hrvatskog jezika. ✔
On želi da upiše tečaj hrvatskog jezika. ✖ in standard Croatian

What is the difference between upisati, upisati se, and upisivati?

These forms are closely related but not identical.

upisati – perfective, transitive
- basic meaning: to write in, to enter, to enroll (something)
- Focuses on a single completed action.
- Example: On želi upisati tečaj. – He wants to enroll in the course (viewed as one complete act).
upisati se – perfective, reflexive
- upisati + se = to enroll oneself, to sign up
- Usually followed by na
  - accusative:
    - On se želi upisati na tečaj hrvatskog jezika. – He wants to enroll in a Croatian course.
- This is very common in everyday speech when talking about enrolling on some program, school, course, etc.
upisivati – imperfective, transitive
- ongoing or repeated action: to be registering, to keep registering, to register multiple things/people:
- Example: Cijeli dan upisuje nove polaznike. – All day he is enrolling new participants.

For the idea “He wants to sign up for a Croatian course”, many speakers would naturally say:

On se želi upisati na tečaj hrvatskog jezika.

The given sentence On želi upisati tečaj hrvatskog jezika. is grammatically correct and perfectly fine, and you will see similar wording on forms and in official contexts.

Why do we say tečaj hrvatskog jezika and not tečaj hrvatski jezik?

Because tečaj (course) is specified by another noun phrase in the genitive case, meaning “course of X”.

Structure:

upisati tečaj – to enroll in a course (direct object in the accusative: tečaj)
tečaj hrvatskog jezika – course of Croatian language

Here:

tečaj is in the accusative (same form as nominative for an inanimate masculine noun):
- nominative: tečaj
- accusative: tečaj
hrvatskog jezika is genitive singular:
- nominative: hrvatski jezik (Croatian language)
- genitive: hrvatskog jezika (of Croatian language)

In Croatian, you very often express “course of X”, “book about X”, “teacher of X” etc. using the genitive:

tečaj engleskog jezika – English language course
udžbenik hrvatskog jezika – textbook of Croatian
učitelj matematike – teacher of mathematics

So tečaj hrvatskog jezika literally means “course of the Croatian language”, and that is why hrvatskog jezika must be in the genitive, not in the nominative hrvatski jezik.

What are the base forms of hrvatskog jezika, and which case is it?

Dictionary/base forms (nominative singular):

hrvatski – Croatian (adjective)
jezik – language

Together: hrvatski jezik – Croatian language (nominative, used for the subject or for simple naming).

In tečaj hrvatskog jezika, the phrase hrvatskog jezika is:

genitive singular masculine
hrvatski → hrvatskog (or hrvatskoga)
jezik → jezika

So:

Nominative: hrvatski jezik – Croatian language
Genitive: hrvatskog jezika / hrvatskoga jezika – of (the) Croatian language

You can see the pattern:

novi jezik – a new language → novog jezika – of a new language
hrvatski jezik – Croatian language → hrvatskog jezika – of Croatian language

The form hrvatskoga jezika (with -oga) is a slightly more formal/complete version; hrvatskog jezika (with -og) is very common and fully correct.

Why is hrvatskog not capitalized, while Croatian in English is?

Croatian capitalization rules are different from English.

In Croatian:

Names of languages are not capitalized:
- hrvatski jezik – Croatian
- engleski jezik – English
- njemački jezik – German
Derived adjectives like hrvatski, engleski, njemački are normally written with a lowercase initial unless they are part of an official proper name:
- Hrvatska – Croatia (proper name, capital H)
- hrvatski građani – Croatian citizens (lowercase)
- Hrvatski sabor – Croatian Parliament (proper name, capital H in the first word of the name)

So hrvatskog jezika is correctly written with a small h.

Is the word order fixed? Could I say On želi tečaj hrvatskog jezika upisati or On želi upisati hrvatskog jezika tečaj?

Croatian word order is fairly flexible, but not every permutation sounds natural.

Neutral, most natural version:

On želi upisati tečaj hrvatskog jezika.

Moving the object for emphasis:

Tečaj hrvatskog jezika želi upisati. – Emphasis on the course itself.
On tečaj hrvatskog jezika želi upisati. – Also possible, with special emphasis.

Infinitive at the end:

On želi upisati tečaj hrvatskog jezika. – preferred
On želi tečaj hrvatskog jezika upisati. – can be used for stylistic/emphatic effect, but much less common in everyday speech.

What usually does not sound natural:

On želi upisati hrvatskog jezika tečaj. – wrong order inside the noun phrase
- the noun (tečaj) should come before its genitive modifier (hrvatskog jezika)

Inside tečaj hrvatskog jezika, the normal order is:

[Noun] + [Genitive phrase]
→ tečaj hrvatskog jezika, udžbenik engleskog jezika, učitelj matematike, etc.

Reversing that to hrvatskog jezika tečaj would only make sense in very marked, poetic, or special emphatic styles, not in neutral speech.

How would I say simply He wants to study Croatian without mentioning a course?

You would normally drop tečaj and jezik and just use the verb učiti or naučiti with the language name in the accusative:

On želi učiti hrvatski. – He wants to study Croatian.
Želi učiti hrvatski. – He wants to study Croatian.

For the idea of achieving knowledge (learn it fully), you can also say:

On želi naučiti hrvatski. – He wants to learn Croatian. (focus on reaching the goal, perfective)

So:

učiti hrvatski – to study/learn Croatian (process)
naučiti hrvatski – to learn Croatian (reach the point of knowing it)

How can I put this sentence into the past or talk about the future?

The present tense with a perfective infinitive already suggests a future result:

On želi upisati tečaj hrvatskog jezika. – He wants to enroll (at some future/unspecified time).

For the past (he wanted), you use the past tense of željeti:

On je želio upisati tečaj hrvatskog jezika. – He wanted to enroll in a Croatian language course.
- želio – masculine
- željela – feminine: Ona je željela upisati…

If you want to say he enrolled (he actually did it), you usually put upisati in the past:

On je upisao tečaj hrvatskog jezika. – He enrolled in a Croatian language course.
On se je upisao na tečaj hrvatskog jezika. / more commonly On se upisao na tečaj hrvatskog jezika.

For the future (he will enroll):

On će upisati tečaj hrvatskog jezika. – He will enroll in a Croatian language course.

The future of želi (će željeti) is possible but rare, just like in English he will want to enroll, which is not very common.

If I say On se želi upisati na tečaj hrvatskog jezika, where does se have to go?

Se is an unstressed clitic pronoun and must appear in the so‑called second position in the clause (after the first stressed word or phrase). In this sentence, correct placements are:

On se želi upisati na tečaj hrvatskog jezika.
Želi se upisati na tečaj hrvatskog jezika.

Incorrect placements:

✖ On želi se upisati na tečaj…
✖ On želi upisati se na tečaj…

So, if you use the reflexive version (which is very natural here), say:

On se želi upisati na tečaj hrvatskog jezika.
or simply
Želi se upisati na tečaj hrvatskog jezika.

How do you pronounce On želi upisati tečaj hrvatskog jezika?

Approximate pronunciation with English‑like hints (stressed syllables in capitals):

On – like on in on top (short o)
želi – ZHEH‑lee
- ž like s in measure
- stress on the first syllable
upisati – oo‑PEE‑sah‑tee
- all vowels are clear and short
tečaj – TEH‑chai
- č like ch in church
- j like y in yes
hrvatskog – hr‑VAHTS‑kog
- r is rolled
- ts as in cats
jezika – YEH‑zee‑kah

Put together, something like:

On ZHEH‑lee oo‑PEE‑sah‑tee TEH‑chai hr‑VAHTS‑kog YEH‑zee‑kah.

All letters are pronounced; there are no silent letters in Croatian.