Learn Hardcore Croatian: Želimo se prijaviti na besplatan tečaj hrvatskog jezika sutra. - We want to register for a free Croatian language course tomorrow.

prijaviti se – to register / sign up (yourself)
- Želimo se prijaviti na tečaj. – We want to sign up for the course.
prijaviti (nekoga/nešto) – to report / to register someone or something (else)
- Želimo prijaviti problem. – We want to report a problem.
- Želim prijaviti sina na tečaj. – I want to sign my son up for the course.

Without se, Želimo prijaviti na besplatan tečaj… is ungrammatical, because prijaviti then needs a direct object (what/who you are registering), not just na + tečaj.

So here se does not really “mean” anything in English; it just shows that we are the ones being registered.

Why is it prijaviti se na tečaj, and not prijaviti se za tečaj or something else?

In standard Croatian, the usual construction for sign up for a course/event is:

prijaviti se na + accusative
- prijaviti se na tečaj – to sign up for a course
- prijaviti se na ispit – to register for an exam
- prijaviti se na natječaj – to apply for a competition / job call

People do sometimes say prijaviti se za tečaj, and you will hear it, but with tečaj / ispit / natječaj etc., na is the most natural and normatively preferred preposition.

So Želimo se prijaviti na besplatan tečaj… is the standard, “textbook” form.

What case is na besplatan tečaj in, and why that case?

Tečaj here is in the accusative singular:

nominative: tečaj (subject form)
accusative: tečaj (same form for masculine inanimate nouns)

The adjective besplatan also takes the accusative masculine singular form:

nominative: besplatan tečaj
accusative: besplatan tečaj (same ending)

The preposition na can take:

accusative = direction / movement / goal (onto, to, for)
locative = location / being “on” or “at” (on, at)

Here we have a goal: sign up *for a course, so it’s *na + accusative:

Idem na tečaj. – I am going to the course. (direction)
Prijavljujem se na tečaj. – I am signing up for the course. (goal)

If we were just talking about being somewhere, we would use na + locative:

Sam na tečaju. – I am at the course. (no movement)

Why is it hrvatskog jezika and not hrvatski jezik?

Because hrvatskog jezika is in the genitive, used here to mean “of Croatian (language)”.

The pattern is:

tečaj + genitive = course of X
- tečaj hrvatskog jezika – (a) course of Croatian (language)
- tečaj engleskog jezika – English language course
- tečaj informatike – computer science / IT course

Forms:

nominative: hrvatski jezik (Croatian language)
genitive: hrvatskog jezika (of Croatian language)

So it’s literally “a free course of Croatian language”, which in natural English we say as “a free Croatian language course”.

Why is hrvatskog not capitalised, even though Croatian is capitalised in English?

Croatian capitalisation rules differ from English:

Names of countries, peoples, and languages:
- Hrvatska – Croatia (capitalised)
- Hrvat – a Croat (capitalised)
- Hrvatica – a Croatian woman (capitalised)
Adjectives derived from them are lower-case:
- hrvatski jezik – Croatian language
- hrvatska glazba – Croatian music
- hrvatskog jezika – of the Croatian language

So hrvatskog is an adjective, not a noun, so it stays lower-case.

Why is there no mi (we) in the sentence? Could I say Mi želimo se prijaviti…?

In Croatian, subject pronouns (ja, ti, on, mi, vi, oni) are usually omitted because the verb ending already shows the person and number.

Želimo se prijaviti…
The ending -imo on želimo clearly marks we.

You only add mi for emphasis or contrast:

Mi želimo se prijaviti, ali oni ne žele.
We want to sign up, but they don’t.

Also, be careful with the position of se:

natural / correct: Mi se želimo prijaviti…
unnatural/wrong: Mi želimo se prijaviti…

The clitic se must come in the so‑called “second position” in the clause, right after the first stressed word (here Mi or Želimo).

Why is the word order Želimo se prijaviti…, not Želimo prijaviti se…?

Croatian has special placement rules for clitics (short unstressed words like se, ga, mi, ti, sam, si…). In most simple clauses, clitics go in second position.

In your sentence, the first stressed word is Želimo, so se comes immediately after it:

Želimo se prijaviti… ✅

Putting se after the infinitive prijaviti:

Želimo prijaviti se… ❌ (sounds wrong / very unnatural)

So the reflexive se attaches early in the clause, not directly to the infinitive, even though logically it “belongs” with prijaviti.

Why is the time word sutra at the end? Could I put it at the beginning?

Yes, you can move sutra quite freely. Croatian word order is flexible and often used for emphasis or style.

All of these are grammatically correct, with slightly different emphasis:

Želimo se prijaviti na besplatan tečaj hrvatskog jezika sutra.
Neutral: we want to sign up tomorrow.
Sutra se želimo prijaviti na besplatan tečaj hrvatskog jezika.
Emphasis on tomorrow (as opposed to another day).
Želimo se sutra prijaviti na besplatan tečaj hrvatskog jezika.
Neutral, but with a small focus on when we want to sign up.

Placing sutra at the end is very common and natural when you’re just adding the time as extra information.

Why is besplatan tečaj and not besplatni tečaj? What’s the difference?

Croatian adjectives have two main types of forms in the masculine singular:

indefinite form (here: besplatan)
definite form (here: besplatni)

The difference is subtle and not always strongly felt today, but roughly:

indefinite = some, not‑previously‑specified thing
definite = a specific, known, or “the mentioned” thing

In practice:

besplatan tečaj – a free course (any such course; neutral here)
besplatni tečaj – that particular free course / the free course (more “definite”)

In your sentence, besplatan tečaj is the most natural version. Using besplatni tečaj wouldn’t be wrong, but it might sound a bit more like “that free course (we know about)” in some contexts.

Why do we use the infinitive prijaviti (se) after želimo instead of a structure with da, like da se prijavimo?

Both patterns exist and are common:

modal verb + infinitive
- Želimo se prijaviti na tečaj.
  We want to sign up for the course.
verb + da + finite verb
- Želimo da se prijavimo na tečaj.
  Literally: We want that we (should) sign up for the course.

Differences:

With verbs like htjeti, željeti, morati, trebati, the infinitive construction is very common and usually a bit shorter and more neutral.
The da + finite verb version can sometimes sound a bit more “spoken” or add a slight nuance of intention, but in many cases they’re interchangeable.

So:

Želimo se prijaviti na besplatan tečaj hrvatskog jezika sutra. – completely natural and probably the most typical choice here.

What’s the aspect of prijaviti (se), and what would prijavljivati (se) mean here?

Prijaviti (se) is perfective:

it focuses on a single, completed act of signing up.
Želimo se prijaviti… – We want to (successfully) sign up (once).

Prijavljivati (se) is imperfective:

it focuses on an ongoing, repeated, or habitual action.
Često se prijavljujemo na razne tečajeve. – We often sign up for various courses.

In your sentence, you’re talking about one specific act tomorrow, so the perfective prijaviti se is exactly right:

Želimo se prijaviti na besplatan tečaj hrvatskog jezika sutra. ✅
(We want to do this one concrete action tomorrow.)