Learn Hardcore Croatian: Na zidu ureda visi velika slika na kojoj piše da moramo čuvati okoliš. - On the office wall there is a big picture on which it says that we must protect the environment.

Na zidu = on the wall
- na
  - locative is used for location (where something is):
    - nominative: zid
    - locative: (na) zidu
ureda = of the office
- This is just a normal genitive of possession:
  - nominative: ured (office)
  - genitive: ureda (of the office)

So the structure is:
Na zidu ureda = on the wall of the office

The preposition na only governs zidu. The second noun ureda depends on zid (wall), not on the preposition.

Could we also say Na zidu u uredu? How is that different from Na zidu ureda?

Yes, Na zidu u uredu is also possible, but the nuance changes slightly.

Na zidu ureda
Literally: On the wall of the office.
→ Emphasis on whose wall it is (the wall belongs to the office).
Na zidu u uredu
Literally: On the wall in the office.
→ Emphasis on where the wall is (a wall located inside the office).

In everyday language, both will often refer to the same thing (a wall in that office), but:

Na zidu ureda sounds a bit more compact and formal, like “the office wall”.
Na zidu u uredu sounds a bit more descriptive, like “on the wall in the office”.

Both are grammatically correct.

Why is the verb visi used? Could I say je or ima instead?

Visi is from visiti = to hang. It describes how the picture is positioned: it is hanging.

Na zidu ureda visi velika slika.
→ On the office wall hangs a large picture. (focus on the way it is placed)

You can also say:

Na zidu ureda je velika slika.
→ There is a large picture on the office wall. (just existence/location)
Na zidu ureda ima velika slika.
→ Much less natural here; ima is usually used in “there is / there are” sentences without a specific subject (U sobi ima stol = There is a table in the room). With a specific, defined thing like velika slika, Croatian prefers je or a more specific verb like visi.

So visi is the most natural if you want to convey that the picture is literally hanging on the wall.

Why is it velika slika and not veliki slika?

Because slika (picture) is feminine, and the adjective must agree with the noun in gender, number, and case.

slika – feminine, singular, nominative
Adjective velik in feminine singular nominative is velika.

Patterns:

masculine: velik zid (a big wall)
feminine: velika slika (a big picture)
neuter: veliko stablo (a big tree)

So veliki slika is incorrect because veliki is a masculine (or plural) form, and it doesn’t match the feminine noun slika.

What does na kojoj mean, and why is it kojoj?

Na kojoj literally means “on which” and it introduces a relative clause describing the picture.

slika na kojoj piše…
→ the picture *on which it says…*

Kojoj is a form of the relative pronoun koji/koja/koje (who/which/that), and it must:

Agree with “slika” in gender and number
- slika is feminine singular
- so we choose the feminine singular form: koja (base form)
Take the case required by its role in the relative clause
In the clause na kojoj piše, the pronoun is the object of the preposition na, so it must be in the locative:
- feminine singular locative of koja is kojoj.

Hence: na kojoj = on which (picture).

Why is piše used without a subject to mean “it says / it is written”?

In Croatian, piše (3rd person singular of pisati = to write) is often used impersonally to mean:

“it says”
“it is written”

For example:

Na vratima piše “Gurati”.
→ On the door it says “Push”.

In such sentences:

There is no explicit subject like English “it”.
The verb is just in 3rd person singular, and the subject is understood from context (often the sign, text, or message).

So:

na kojoj piše da moramo čuvati okoliš
literally: on which writes that we must protect the environment,
but idiomatically: on which *it says that we must protect the environment*.

What does da do in piše da moramo čuvati okoliš?

Da here is a conjunction that introduces a content clause, similar to English “that”.

piše da moramo čuvati okoliš
→ it says *that we must protect the environment.*

Structure:

Main clause: piše (it says / it is written)
Subordinate clause introduced by da: da moramo čuvati okoliš
(that we must protect the environment)

This da + clause construction is extremely common in Croatian after verbs like reći (to say), misliti (to think), pisati (to write), znati (to know), etc.:

Rekao je da dolazi. – He said (that) he is coming.
Piše da je sastanak u 3. – It says (that) the meeting is at 3.

Why is there no pronoun mi (“we”) before moramo?

In Croatian, subject pronouns like ja, ti, on, mi, vi, oni are usually dropped because the verb endings already show the person and number.

moram – I must
moraš – you (sg.) must
mora – he/she/it must
moramo – we must
morate – you (pl.) must
moraju – they must

So:

moramo čuvati okoliš already clearly means “we must protect the environment”.
Mi moramo čuvati okoliš is also correct, but adds emphasis on we (“we must protect the environment”, maybe in contrast to others).

Why is čuvati (infinitive) used after moramo? Could we say čuvamo or sačuvati instead?

After modal verbs like morati (must), htjeti (want), moći (can), Croatian uses the infinitive:

moramo čuvati – we must protect
želimo čuvati – we want to protect
možemo čuvati – we can protect

So moramo čuvati okoliš is the normal structure: modal verb + infinitive.

About the other options:

moramo čuvamo okoliš – incorrect (you don’t follow moramo with a finite verb form).
moramo sačuvati okoliš – grammatically correct, but sačuvati is perfective and suggests a single, complete achievement (“we must succeed in preserving the environment”).
čuvati is imperfective and is better for a general, ongoing obligation: we must continually take care of the environment.

Here, the general rule/obligation fits better with čuvati (imperfective).

What case is okoliš in, and why does it look like the dictionary form?

Okoliš is in the accusative singular, functioning as the direct object of čuvati.

Verb: čuvati – to protect, guard, preserve
Question: čuvati koga/što? – protect whom/what?
Answer: okoliš – the environment → direct object → accusative.

For many masculine inanimate nouns, the accusative singular = nominative singular, so the form doesn’t change:

nominative: okoliš – the environment
accusative: okoliš – (to protect) the environment

Compare with an animate masculine:

nominative: čovjek – man
accusative: čovjeka – (vidim) čovjeka – I see the man

So okoliš looks like the dictionary form, but its function in the sentence tells you it’s in the accusative.

Is okoliš exactly the same as “environment”? Are there other words I should know?

Okoliš generally corresponds to “the environment” in the sense of nature / the natural environment, especially in ecological contexts.

čuvati okoliš – protect the environment (ecology, pollution, climate, etc.)

Other related words:

priroda – nature (trees, mountains, animals, etc.)
- čuvati prirodu – protect nature
okruženje – surroundings, environment in a broader or more abstract sense
- radno okruženje – work environment
- obiteljsko okruženje – family environment

In this sentence, okoliš is the standard word used in slogans and texts about environmental protection.

Can the word order be different, for example: Velika slika visi na zidu ureda na kojoj piše…?

Yes, Croatian word order is relatively flexible, but not all permutations sound equally natural.

Possible and natural variants include:

Na zidu ureda visi velika slika na kojoj piše…
(original: starts with the location)
Velika slika visi na zidu ureda na kojoj piše…
(starts with the subject “a large picture”)

Both are grammatical. The main effects of changing the order are:

Focus / emphasis – what you put near the beginning is often what you want to highlight (location vs. the picture itself).
Rhythm / style – some orders simply sound smoother to native speakers.

However, you should keep closely related elements together:

velika slika (adjective + noun)
na zidu ureda (preposition + its phrase)
na kojoj piše… (relative clause right after slika, which it describes)

Breaking these groups apart too much would sound awkward.

In na kojoj piše, why do we repeat na? Why not just kojoj piše?

In Croatian, prepositions must stand directly in front of the word they govern. They cannot be left “stranded” as in English.

In English, you can (informally) say:

the picture which it says on …
(preposition on is separated from which)

In Croatian, that is not possible. The preposition must stay attached to the pronoun:

slika na kojoj piše… – the picture on which it says…

So:

na kojoj piše – correct
kojoj piše – would mean “to which it writes” (governed by nothing), and does not express “on which”.

Even though we already had a na earlier in Na zidu ureda, that one belongs to zidu, not to kojoj, so we must use na again in the relative clause: na kojoj.

Could we also say slika na kojoj je napisano da moramo čuvati okoliš instead of na kojoj piše da…? Is there a difference?

Yes, you can say:

slika na kojoj je napisano da moramo čuvati okoliš

Both forms are grammatically correct, but there is a nuance:

na kojoj piše da…
- Uses piše (imperfective, present) in an impersonal way.
- Sounds very natural and common in everyday language.
- Neutral style: “on which it says that…”
na kojoj je napisano da…
- Uses je napisano (passive, perfective).
- Slightly more formal or bookish in tone.
- Emphasises the result of the act of writing: “on which it has been written that…”

In most everyday contexts (signs, posters, slogans), natives will naturally say na kojoj piše da….