Learn Hardcore Croatian: Kad učim, stavljam slušalice i slušam tihi zvuk mora. - When I study, I put on headphones and listen to the quiet sound of the sea.

Kad učim, pijem kavu. – When I (usually) study, I drink coffee.
Ne zovi me kad učim. – Don’t call me when I am studying (right now / in general).

What is the difference between kad and kada? Can I say Kada učim instead?

Kad and kada mean the same thing: when.

kad – shorter, more colloquial, very common in speech and in informal writing
kada – a bit more formal or emphatic, common in writing, but also used in speech

You can absolutely say:

Kad učim, stavljam slušalice…
Kada učim, stavljam slušalice…

Both are correct and sound natural; the meaning doesn’t change.

Why is there a comma after Kad učim?

Croatian uses a comma after a dependent clause (subordinate clause) that comes before the main clause.

Dependent clause: Kad učim = When I study
Main clause: stavljam slušalice i slušam tihi zvuk mora = I put on headphones and listen to the quiet sound of the sea.

So the structure is:

Kad učim, / stavljam slušalice i slušam tihi zvuk mora.

If the order is reversed and the main clause comes first, the comma is usually not used:

Stavljam slušalice i slušam tihi zvuk mora kad učim.

Why is there no I (ja) in the sentence? How do I know it means “I”?

In Croatian, the personal pronoun is often dropped because the verb ending already shows the person.

učim – I study (1st person singular)
stavljam – I put
slušam – I listen

You only say ja (I) if you want to emphasize it:

Ja učim, a ti se igraš. – I am studying, and you are playing.

So the full version could be:

Kad ja učim, ja stavljam slušalice i slušam tihi zvuk mora.
…but that sounds heavy and over‑emphatic. The natural version is to omit ja.

What is the difference between učim and studiram? Could I say Kad studiram?

Both translate as “I study”, but they’re used differently.

učiti – to learn, to study (anything: for a test, a language, playing piano, etc.)
- Učim hrvatski. – I’m learning Croatian.
- Učim za ispit. – I’m studying for an exam.
studirati – to study at a university; to be enrolled in a major or field
- Studiram medicinu. – I’m studying medicine (I’m a med student).
- Ona studira pravo. – She studies law.

In your sentence, Kad učim is best because you’re talking about the activity of learning / studying, not about your field of study as a university student. You could say Kad studiram only if you specifically meant “When I am doing my university studies,” but even then, kad učim is more neutral and more common for the act of studying itself.

What is the difference between stavljam and stavim?

Both come from staviti (“to put”), but:

stavljam – imperfective, present tense
- stresses the ongoing or repeated action
- Kad učim, stavljam slušalice. – Whenever I study, I put on headphones (habit).
stavim – perfective, present form with a future meaning (“I will put”) or used in some constructions
- Ako učim, stavim slušalice. – If I study, I (will) put on headphones. (This sounds more like “whenever X happens, then I do Y as a complete action.”)

For habitual actions (“Every time I study, I put on headphones”), stavljam (imperfective) is the most natural choice.

Should the verb staviti be reflexive here, like stavljam si slušalice?

Both forms are possible:

stavljam slušalice
- literally: “I put (the) headphones (on).”
- understood as putting them on yourself from context
stavljam si slušalice
- literally: “I put headphones on myself.”
- a bit more explicit, but can sound slightly more colloquial or region‑dependent

In everyday speech, stavljam slušalice is completely natural and common. You do not have to use the reflexive here.

Why is slušalice plural? What is the singular?

In Croatian, slušalice is normally plural, just like headphones in English.

slušalica – singular, “earpiece” / “earphone” (one piece)
slušalice – plural, “headphones”

Since you usually use two earpieces, speakers almost always say:

stavljam slušalice – I put on headphones.

Grammatically in this sentence:

slušalice is accusative plural (direct object of stavljam).

What cases appear in tihi zvuk mora and why mora, not more?

tihi zvuk mora = the quiet sound of the sea

zvuk – “sound”
tihi – “quiet” (adjective)
more – “sea” (nominative / accusative)
mora – “of the sea” (genitive singular)

Cases:

tihi zvuk – accusative singular masculine
- It’s the direct object of slušam: I listen to what? → tihi zvuk
mora – genitive singular
- Shows a “of” relationship: the sound of the sea
- This is why we use mora, not more.

Pattern:

zvuk glazbe – the sound of music
miris kave – the smell of coffee
tihi zvuk mora – the quiet sound of the sea

Why is it tihi zvuk, not tiho zvuk or tih zvuk?

The adjective must agree with the noun in gender, number, and case.

zvuk is masculine singular. In this sentence it’s in the accusative (object of slušam).
For a masculine singular noun in such a context (animate vs inanimate matters, but zvuk is inanimate), the adjective form is tihi.

So:

tihi zvuk – the quiet sound
glasan zvuk – the loud sound

Tiho is an adverb (“quietly”), not the correct form here:

tiho – quietly
- Tiho pričam. – I speak quietly.

tih is another adjective form, used in different cases or patterns:

tih zvuk can occur in some contexts (e.g. after certain prepositions or in different case usage), but tihi zvuk is the correct form here in standard style. Many speakers will alternate, but for learners, tihi zvuk is the safe, textbook form in this sentence structure.

Could I say slušam tiho more instead of slušam tihi zvuk mora?

You can, but the meaning changes:

slušam tihi zvuk mora
- literally: “I listen to the quiet sound of the sea.”
- Focus is on the sound itself.
slušam tiho more
- literally: “I listen to the sea, (which is) quiet.”
- Here tiho is an adverb or acts more like “quietly,” describing how the sea sounds or how you are listening.
- It sounds more poetic or stylistically marked.

The original sentence emphasizes the sound (zvuk), which is why tihi zvuk mora is used.

Why is slušam used, not something like “I hear” or another verb?

Croatian uses slušati for “to listen (to)”, just like English:

slušam glazbu – I listen to music
slušam učitelja – I listen to the teacher
slušam tihi zvuk mora – I listen to the quiet sound of the sea

If you wanted to say “I hear”, you would use:

čuti – to hear
- Čujem zvuk mora. – I hear the sound of the sea.

In your sentence, the idea is that you intentionally listen, so slušam is the right verb.

Can I change the word order? For example, Kad učim, slušam tihi zvuk mora i stavljam slušalice?

Yes, Croatian word order is relatively flexible, and both of these are correct:

Kad učim, stavljam slušalice i slušam tihi zvuk mora.
Kad učim, slušam tihi zvuk mora i stavljam slušalice.

The meaning is practically the same. The first position after the comma often carries a bit more emphasis, so in the original version the speaker slightly emphasizes putting on headphones first, then listening. In everyday speech, either order sounds fine.

Is this sentence talking about a habit or about something happening right now?

By default, this sentence is understood as a habitual action:

Kad učim, stavljam slušalice i slušam tihi zvuk mora.
→ Whenever I study, I put on headphones and listen to the quiet sound of the sea.

The present tense in Croatian often expresses:

general truths
routines and habits
actions happening right now

Context would decide if it’s about this very moment, but without extra context, listeners will usually take it as your study habit.