Learn Hardcore Croatian: Da sam ranije upisao ovaj tečaj, danas bih već bolje govorio hrvatski. - If I had enrolled in this course earlier, today I would already speak Croatian better.

The structure da + biti (in the present) + past participle is a very common way to express an unreal or counterfactual condition in the past in Croatian.

Da sam ranije upisao ovaj tečaj = If I had enrolled in this course earlier (but I didn’t).
It introduces a hypothetical, something that is contrary to reality.

In English you use “if” plus past perfect:

If I had enrolled earlier…

In Croatian, using da sam plus a past participle (upisao) plays the same role. It tells us that the action did not actually happen, but we are imagining the consequence.

What grammatical form is sam upisao and why is sam separated from upisao?

Sam upisao is part of the past tense (perfect) of the verb upisati (to enroll).

sam = 1st person singular of biti (to be)
upisao = past participle, masculine singular of upisati

Together, they form the past tense:

upisao sam / sam upisao = I enrolled

In neutral word order, you’ll usually see:

Ja sam upisao ovaj tečaj.

But in complex sentences like this, clitics (short forms like sam, bih, ga, se…) often move to the second position in the clause (a typical Slavic feature), so:

Da sam ranije upisao ovaj tečaj…

Here, sam is in the second position of the clause da sam ranije upisao ovaj tečaj. The meaning doesn’t change; it’s still “had enrolled” / “I enrolled” in a past, completed sense.

Why do we use upisao (perfective) and not something like upisivao?

Croatian distinguishes aspect:

upisati – perfective (focus on a completed action: to enroll, finish the enrollment)
upisivati – imperfective (focus on a repeated / ongoing process: to be enrolling, used to enroll, etc.)

In a sentence like:

Da sam ranije upisao ovaj tečaj…

we are talking about one completed, decisive action: enrolling in the course. That clearly calls for a perfective verb (upisao).

If you said:

Da sam ranije upisivao ovaj tečaj…

it would sound strange, as if you were repeatedly or continuously enrolling in it, which doesn’t fit the usual meaning.

Why is it upisao and not upisala or something else?

The form of the past participle (upisao / upisala / upisali …) must agree in gender and number with the subject.

upisao – masculine singular
upisala – feminine singular
upisalo – neuter singular
upisali – masculine or mixed plural
upisale – feminine plural

Your sentence is in the voice of a male speaker:

Da sam ranije upisao ovaj tečaj… (spoken by a man)

If a woman said it, she would say:

Da sam ranije upisala ovaj tečaj, danas bih već bolje govorila hrvatski.

So:

change upisao → upisala
and govorio → govorila to match the feminine subject.

What is the role of bih in danas bih već bolje govorio hrvatski? Why not bi?

Bih is the first-person singular conditional form of biti (to be) and is used to form the conditional mood in Croatian.

Forms of the conditional auxiliary are:

bih – I would
bi – you (sg.), he, she, it would
bismo – we would
biste – you (pl.) would
bi – they would

So:

Ja bih govorio = I would speak
On bi govorio = He would speak

In your sentence:

danas bih već bolje govorio hrvatski
= today I would already speak Croatian better

We use bih (not bi) because the implied subject is “I” (first person singular).

Is bih govorio a “tense” like in English? How does this conditional form work?

In Croatian, bih + past participle is the basic conditional form (often called kondicional I).

Structure:

bih + govorio
bi + govorio
bismo + govorili, etc.

Examples:

Govorio bih hrvatski. – I would speak Croatian.
Danas bih već bolje govorio hrvatski. – Today I would already speak Croatian better.

In your full sentence, the pattern is:

Unreal condition in the past: Da sam ranije upisao ovaj tečaj…
Hypothetical result in the present: …danas bih već bolje govorio hrvatski.

So it corresponds very closely to English “If I had done X, I would now do/be Y.”

Which case is ovaj tečaj in, and why? Why not ovog tečaja?

Ovaj tečaj is in the accusative singular (masculine), used here as the direct object of upisao.

Verb: upisati (to enroll in something)
It takes a direct object in the accusative: upisati + što?

Declension of ovaj tečaj (masc. sg.):

Nominative: ovaj tečaj – this course (subject)
Accusative: ovaj tečaj – this course (object)
Genitive: ovog tečaja – of this course

In your sentence:

Da sam ranije upisao ovaj tečaj…

ovaj tečaj answers “enrolled what?” → direct object → accusative, which for this masculine noun looks the same as nominative.

Ovog tečaja (genitive) would mean “of this course”, not correct here.

What does već add in danas bih već bolje govorio hrvatski? Can I move it somewhere else?

Već most often means already here. It implies that by now, at this point in time (today), the improvement would have happened.

danas bih već bolje govorio hrvatski
= today I would already speak Croatian better

It suggests that a certain amount of time has passed, enough for progress to be visible.

As for word order, već is quite flexible. You can say:

Danas bih već bolje govorio hrvatski. (most natural)
Danas bih govorio već bolje hrvatski.
Već bih danas bolje govorio hrvatski.

The basic meaning stays the same; moving već can slightly shift emphasis (e.g. more on “already today” vs “already speak better”), but all are understandable and acceptable in everyday speech. The original word order is the most neutral.

Why is it govorio hrvatski and not govorio na hrvatskom? Are both correct?

Both govoriti hrvatski and govoriti na hrvatskom are used, but they’re slightly different in focus:

govoriti hrvatski
- Literally: to speak Croatian
- Uses hrvatski as a direct object (accusative) – speak what?
- Common when talking about ability / skill in a language.
- Danas bih već bolje govorio hrvatski.
  → focuses on your knowledge of the language itself.
govoriti na hrvatskom
- Literally: to speak in Croatian
- Uses a prepositional phrase with na + locative.
- Often used when talking about the language you’re currently using in a specific situation:
  - Možemo li govoriti na hrvatskom? – Can we speak in Croatian?

In your sentence, you’re speaking about how well you would know/speak the language in general, so govoriti hrvatski is more natural.
Govoriti na hrvatskom wouldn’t be wrong, but it slightly shifts towards “speaking in Croatian (as the medium)” rather than “knowing Croatian better as a language.”

Is there any difference between ranije and prije here? Could I say Da sam prije upisao ovaj tečaj?

You could say:

Da sam prije upisao ovaj tečaj…

and it would still be understandable and acceptable in many contexts.

Subtle difference:

ranije – earlier (comparative of rano – early); relative, often used with an implied reference point (earlier than now / earlier than planned).
prije – before / earlier; also a preposition: prije tečaja, prije dvije godine, etc.

In this sentence:

Da sam ranije upisao ovaj tečaj…
→ emphasizes “earlier than I actually did” or “earlier in time” in a slightly more neutral way.

Prije is slightly more bare and might sound like something is missing unless context is very clear (earlier than what?). In real speech, Croatians do say both, but ranije often feels a bit more natural in a standalone conditional like this.

Can I reverse the clause order and say: Danas bih već bolje govorio hrvatski, da sam ranije upisao ovaj tečaj?

Yes, you can. Word order of main clause and conditional clause is flexible in Croatian:

Da sam ranije upisao ovaj tečaj, danas bih već bolje govorio hrvatski.
Danas bih već bolje govorio hrvatski, da sam ranije upisao ovaj tečaj.

Both are correct and mean the same.

Typical patterns:

[Condition], [Result]. – very common, especially in writing.
[Result], [Condition]. – also common, often in speech when the speaker first states the hypothetical outcome and then gives the unreal condition.

So in this case, switching the order is a matter of style and emphasis, not grammar correctness.

Could I say pričao hrvatski instead of govorio hrvatski? Is there a difference?

You could say it, but it changes the nuance:

govoriti hrvatski – to speak Croatian (as a language), to know/use the language; neutral, standard verb for speaking a language.
pričati – to talk, to tell, to chat, to narrate; more about telling stories / chatting, not about language ability itself.

So:

Danas bih već bolje govorio hrvatski.
→ Today I would already speak Croatian better (my skill in the language would be better).
Danas bih već bolje pričao hrvatski.
→ sounds like I would already talk better in Croatian / tell things better in Croatian; more informal, focusing slightly more on your style of talking rather than the language competence itself.

For talking about language ability, govoriti hrvatski is definitely the most natural and standard choice.