Learn Hardcore Croatian: Sljedeći tjedan imam važan ispit iz hrvatskog. - Next week I have an important exam in Croatian.

Sljedeći – next (adjective, masculine singular, nominative)
tjedan – week (noun, masculine singular, nominative)
→ Together: Sljedeći tjedan = next week
imam – I have (1st person singular, present tense of imati = to have)
važan – important (adjective, masculine singular, accusative form, which for masc. inanimate looks like nominative)
ispit – exam (noun, masculine singular, accusative; identical to nominative for inanimate masculine nouns)
→ Together: važan ispit = an important exam
iz – from / in (the subject of) – here it means in (a school subject) and governs the genitive case
hrvatskog – Croatian (language) in the genitive masculine singular (short for hrvatskog jezika)

Literal-style gloss:
Next week I-have important exam from-Croatian.
Natural English: Next week I have an important Croatian exam / an important exam in Croatian.

Why is it Sljedeći tjedan and not something like Sljedećeg tjedna? What case is used for “next week”?

Sljedeći tjedan is in the nominative case and is used as a kind of time expression without a preposition.

Croatian often uses bare nominative time expressions to say when something happens, especially for:

Ovaj tjedan – this week
Sljedeći tjedan – next week
Prošli tjedan – last week
Sljedeći ponedjeljak – next Monday

You can see genitive with a preposition:

Sljedećeg tjedna – during next week / in the course of next week

This sounds a bit more formal or emphasizes the whole period of the week.
But for a simple “Next week I have an exam”, Sljedeći tjedan (nominative) is the most natural choice.

Why is it imam and not a future form like imat ću? Does this still mean a future event?

Yes, imam is grammatically present tense, but in Croatian the present is very often used for scheduled future events, similar to English:

English: I have an exam next week. (present, future meaning)
Croatian: Imam ispit sljedeći tjedan.

You could also say:

Imat ću važan ispit iz hrvatskog sljedeći tjedan. – I will have an important exam in Croatian next week.

Both are correct. The difference:

Imam
- time expression (sljedeći tjedan) is the most natural way to talk about a fixed arrangement in the near future.
Imat ću focuses more explicitly on futurity, but sounds a bit heavier and less neutral in this very ordinary context.

Why is it važan ispit and not važnu ispit or važni ispit? How does the adjective agree with the noun here?

Ispit (exam) is:

gender: masculine
number: singular
animacy: inanimate

In the sentence it is the direct object of imam, so it’s in the accusative singular.

For masculine inanimate nouns, the accusative form of the adjective is the same as the nominative:

nominative: važan ispit – an important exam
accusative: (imam) važan ispit – I have an important exam

If the noun were masculine animate (a person), the adjective form would change in the accusative, e.g.:

nominative: važan profesor – an important professor
accusative: vidim važnog profesora – I see an important professor

So važan ispit is exactly the correct agreement for an important exam used as a direct object.

What exactly does ispit mean, and how is it different from test?

Both exist in Croatian, but they’re not identical in nuance:

ispit
- Usually a more formal exam: university exams, high-school finals, driver’s license exam, etc.
- Can be oral or written.
- Often a bigger, more “official” assessment.
test
- Often a smaller written test, quiz, or exercise.
- Used informally for school tests, online tests, etc.

In the sentence važan ispit iz hrvatskog, the idea is a significant, probably official exam in the subject of Croatian (e.g. a big school or university exam), not just a little quiz.

Why is it iz hrvatskog and not u hrvatskom or just hrvatski? What does iz do here?

The preposition iz literally means “from / out of”, but with school subjects it’s used in the sense of:

“in (the subject of)”

So:

ispit iz hrvatskog = an exam in Croatian (language)
ispit iz matematike = an exam in math
test iz povijesti = a test in history

Iz always takes the genitive case, which is why hrvatski becomes hrvatskog (genitive masculine singular).

You would not say ispit u hrvatskom for an exam in Croatian as a subject; u hrvatskom would mean inside Croatian in some physical or abstract sense, which is not natural here.

You also can’t just say važan ispit hrvatski the way you can in English (“an important Croatian exam”); in Croatian, you need the preposition iz to show that Croatian is the subject of the exam.

What is hrvatskog exactly? Is it an adjective or a noun? Why does it end in -og?

Hrvatski is originally an adjective: Croatian (adj.).

When we talk about languages, Croatian usually uses the adjective form as a stand‑in for “language”:

hrvatski (jezik) – Croatian (language)
engleski (jezik) – English (language)
njemački (jezik) – German (language)

In grammar terms, this is an adjective used substantively (as a noun).

Because it follows iz, it must be in the genitive singular masculine:

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

The -og ending is the standard genitive masculine singular ending for many adjectives of this type:

dobar → dobrog
novi → novog
hrvatski → hrvatskog

So iz hrvatskog is short for iz hrvatskog jezika – from/of the Croatian language → in Croatian (as a subject).

Could I say iz hrvatskoga instead of iz hrvatskog? Is there a difference?

Yes, iz hrvatskoga is also grammatically correct.

hrvatskog and hrvatskoga are both genitive masculine singular forms of hrvatski.
-oga is a slightly fuller, more traditional form; -og is shorter and more common in everyday speech.

In modern standard Croatian:

iz hrvatskog – most typical and neutral in everyday usage
iz hrvatskoga – slightly more formal or stylistically “full”; you might hear it in careful speech, literature, or more formal contexts

Meaning-wise, they are the same in this sentence.

Can I change the word order? For example, can I say Imam važan ispit iz hrvatskog sljedeći tjedan? Does the meaning change?

Yes, Croatian allows flexible word order, and several variations would be natural:

Sljedeći tjedan imam važan ispit iz hrvatskog.
Imam sljedeći tjedan važan ispit iz hrvatskog.
Imam važan ispit iz hrvatskog sljedeći tjedan.

All essentially mean the same.

Subtle tendencies:

Putting Sljedeći tjedan at the beginning (as in the original) emphasizes the time frame.
Putting imam first keeps a very neutral, statement-like order.
Putting sljedeći tjedan at the end is also fine; it might feel a bit more like an afterthought: “I have an important exam in Croatian, next week.”

None of these sound wrong or unnatural; Croatian word order is strongly guided by what the speaker wants to emphasize rather than strict rules like in English.

Why doesn’t Croatian use any article here (like “a/an/the”)? How do I know if važan ispit means “an important exam” or “the important exam”?

Croatian has no articles (a/an/the). The noun phrase važan ispit simply means “important exam”, without specifying definiteness by a word.

How you interpret it—“an important exam” or “the important exam”—depends on context, not on a separate word:

If this is the first time you mention it, English usually uses “an important exam”.
If both speakers already know which exam is being discussed, English might use “the important exam”.

Croatian doesn’t mark this difference morphologically. You understand it from what has been said before, or from shared knowledge, not from the form of ispit itself.

How do you pronounce sljedeći, especially the slj part, and are there any tricky sounds in this sentence for English speakers?

Approximate pronunciation (with stress marked by bold):

Sljedeći – SLJE-de-chi
- slj is pronounced like slye in fast “sly-eh”, a consonant + lje sequence.
- đ (in sljedeći spelled đ or dž + i in some transliterations, but here it's actually đe) is close to the “j” in “judge”, but softer; in sljedeći, it’s actually đe → like dje.
- ći – chi, like “chee” but shorter and with a softer tʃ sound.

Word by word (rough English approximations):

Sljedeći – /ˈsljɛ.dɛ.t͡ɕi/ → “SLYE-de-chi” (short vowels)
tjedan – /ˈtjɛ.dan/ → “TYE-dan”
imam – /ˈi.mam/ → “EE-mam” (both i and a short)
važan – /ˈʋa.ʒan/ → “VA-zhan”
- ž like the s in “measure”.
ispit – /ˈi.spit/ → “EE-spit” (short i both times)
iz – /iz/ → “eez”
hrvatskog – /xr̩.ˈʋa.tskog/
- Initial hr has a noticeable h (like in “house”) followed by a trilled or tapped r.
- v is closer to English “v/w”, made with the lips, not the teeth.

The trickiest parts for many English speakers:

Clusters slj, tj, hrv, and the rolled/tapped r.
The soft ć in sljedeći, different from hard č.

But even if your pronunciation is a bit “Anglicized”, you’ll still be understood.