Kad prođeš kroz park, vidjet ćeš školu.

Because Croatian often drops subject pronouns when they are clear from the verb ending.

• prođeš = you pass / you go through
• vidjet ćeš = you will see

Both verbs already show 2nd person singular, so ti (you) is not necessary.

You could add ti for emphasis or contrast:

• Kad ti prođeš kroz park, vidjet ćeš školu.

But in a neutral sentence, leaving it out is more natural.

Both kad and kada mean when.

• kad is the shorter, very common everyday form
• kada is a bit fuller and can sound slightly more formal or more deliberate

So both are possible here:

• Kad prođeš kroz park...
• Kada prođeš kroz park...

There is no major difference in meaning in this sentence.

This is a very common Croatian pattern.

In Croatian, after words like kad (when), a perfective present is often used to talk about a future action that will be completed before the main action happens.

So:

• Kad prođeš kroz park literally looks like When you pass/go through the park
• but in meaning it is When you have gone through the park / Once you get through the park

Then the main clause uses the future:

• vidjet ćeš školu = you will see the school

So Croatian does not normally say future tense in both parts here.

This is about aspect.

• proći → perfective
• prolaziti → imperfective

Here, the sentence refers to one completed future action: first you get through the park, then you see the school. That is why Croatian uses the perfective verb:

• Kad prođeš kroz park... = When you get through / once you pass through the park...

If you used prolaziš, it would suggest something more ongoing, repeated, or habitual, which does not fit as well here.

So prođeš is the natural choice because the action is seen as completed.

kroz means through.

The preposition kroz takes the accusative case.

So in kroz park, park is actually in the accusative singular. It just happens to look the same as the nominative because park is an inanimate masculine noun.

That means:

• nominative: park
• accusative: park

Same form, different grammatical role.

This is the future tense in Croatian, called futur I.

It is formed with:

• the infinitive
• plus a present-tense clitic form of htjeti (to want), which functions as a future auxiliary

So:

• vidjeti = to see
• ćeš = you will

When the auxiliary comes after the infinitive, standard Croatian spelling usually drops the final -i of the infinitive:

• vidjeti + ćeš → vidjet ćeš

So vidjet ćeš is correct standard Croatian.

Because in standard Croatian orthography, when the future auxiliary comes after an infinitive ending in -ti, the final -i is dropped.

So:

• vidjeti → vidjet ćeš
• raditi → radit ćeš
• pisati → pisat ćeš

This is just a spelling rule for the future tense.

Another possible word order is:

• Ćeš vidjeti školu. — but this is not normal at the start of a sentence
• Kad prođeš kroz park, školu ćeš vidjeti. — possible, but marked
• Kad prođeš kroz park, vidjet ćeš školu. — the natural neutral version

Also very common is putting the auxiliary before the infinitive in contexts where word order allows it:

• Školu ćeš vidjeti kad prođeš kroz park.

Because školu is the accusative singular of škola.

• škola = nominative, the basic dictionary form
• školu = accusative, used here because it is the direct object of vidjeti (to see)

So:

• vidjeti školu = to see the school

Since the verb see takes a direct object, Croatian uses the accusative.

Because Kad prođeš kroz park is a subordinate clause, and it comes before the main clause.

So Croatian separates them with a comma:

• Kad prođeš kroz park, vidjet ćeš školu.

This is similar to English:

• When you go through the park, you will see the school.

If the order is reversed, the comma may disappear:

• Vidjet ćeš školu kad prođeš kroz park.

Not really. kad means when, not if.

• kad = when
• ako = if

So:

• Kad prođeš kroz park, vidjet ćeš školu. = When you go through the park, you will see the school.
• Ako prođeš kroz park, vidjet ćeš školu. = If you go through the park, you will see the school.

In real usage, the difference can sometimes feel small, especially if the speaker assumes the action is likely. But grammatically, kad is temporal and ako is conditional.

Yes. Croatian word order is fairly flexible.

These are all possible:

• Kad prođeš kroz park, vidjet ćeš školu.
• Vidjet ćeš školu kad prođeš kroz park.

Both mean basically the same thing.

The version with kad first puts the time condition first.
The version with vidjet ćeš školu first sounds a little more direct about what you will see.

Croatian often changes word order for focus, style, or rhythm, but the original sentence is a very natural neutral choice.