Ako majstor ne zatvori tu rupu danas, sutra nećemo moći koristiti roletu.

This is about aspect.

• zatvoriti = perfective, meaning to close / to shut completely, as a finished action
• zatvarati = imperfective, meaning to be closing / to close repeatedly / to close in general

After ako (if), Croatian often uses the present tense of a perfective verb to talk about a future completed action:

• Ako majstor ne zatvori tu rupu danas...
  = If the handyman doesn’t close that hole today...

Even though zatvori looks like a present-tense form, here it refers to a future result in the condition.

If you said ne zatvara, it would sound more like:

• if he isn’t closing it / if he doesn’t usually close it which is not the intended meaning here.

Because Croatian usually does not use a future form after ako in this kind of sentence.

English says:

• If he doesn’t close it today...

Croatian says:

• Ako ne zatvori danas...

So the condition clause uses present form (often with a perfective verb), while the main clause can use the future:

• sutra nećemo moći... = tomorrow we won’t be able...

A very natural Croatian pattern is:

• Ako + present/perfective, future in the main clause

Because the negative future of htjeti (to want, also used to form the future tense) is written together in standard Croatian:

• ću, ćeš, će, ćemo, ćete, će = future auxiliary forms
• negative forms: neću, nećeš, neće, nećemo, nećete, neće

So:

• ćemo = we will
• nećemo = we will not

This is standard spelling, not two separate words.

This is the structure:

• moći = can / to be able
• koristiti = to use

So:

• nećemo moći koristiti roletu = we will not be able to use the shutter/blind

Croatian often uses:

• a conjugated modal verb + infinitive

Here:

• nećemo = future of moći
• moći = infinitive? Actually in this sentence, nećemo is from htjeti, which forms the future with moći
• full structure: nećemo moći koristiti = we will not be able to use

More literally:

• we will-not be-able use

Because rupa (hole) is the direct object of zatvoriti, so it goes into the accusative case.

• nominative: rupa
• accusative: rupu

So:

• zatvoriti rupu = to close the hole

This is a very common feminine noun pattern:

• žena → ženu
• kuća → kuću
• rupa → rupu

For the same reason: the noun is in the accusative, so the demonstrative must match it.

• nominative feminine singular: ta rupa = that hole
• accusative feminine singular: tu rupu = that hole (as an object)

Croatian adjectives and demonstratives agree with the noun in:

• gender
• number
• case

So both words change:

• ta rupa
• tu rupu

Again, this is the accusative case, because roleta is the direct object of koristiti.

• nominative: roleta
• accusative: roletu

So:

• koristiti roletu = to use the shutter/blind

This follows the same feminine pattern as rupa → rupu.

In Croatian, roleta usually refers to a roller shutter or sometimes a roller blind, depending on context and region.

In many everyday situations, especially in Croatia, roleta often means the exterior rolling window shutter found on houses and apartments.

So in this sentence, it most likely means:

• the shutter or
• the roller blind/shutter

The exact English word depends on the situation, but grammatically the Croatian is straightforward.

Literally, majstor can mean master/craftsman, but in everyday Croatian it often means:

• repairman
• handyman
• contractor
• workman
• tradesman

So in this sentence, majstor is probably the person doing repair work.

Depending on context, a natural English translation could be:

• the handyman
• the repairman
• the worker
• the contractor

Because each time word belongs naturally to the part it modifies:

• danas goes with ne zatvori
  = if he doesn’t close it today
• sutra goes with nećemo moći koristiti
  = tomorrow we won’t be able to use it

So the timeline is:

1. today: he should close the hole
2. tomorrow: we want to use the shutter
3. if step 1 does not happen, step 2 becomes impossible

Yes. Croatian word order is fairly flexible, though some orders sound more natural than others.

Original:

• Ako majstor ne zatvori tu rupu danas, sutra nećemo moći koristiti roletu.

Possible variations:

• Ako majstor danas ne zatvori tu rupu, sutra nećemo moći koristiti roletu.
• Sutra nećemo moći koristiti roletu ako majstor danas ne zatvori tu rupu.

These all mean basically the same thing.

The original version sounds natural because:

• the condition comes first
• danas is placed near the action in the if-clause
• sutra is placed at the start of the main clause for emphasis

Because Croatian infinitives do not need a separate marker like English to.

• koristiti already means to use
• zatvoriti already means to close

So:

• moći koristiti = to be able to use not
• moći to koristiti

The infinitive ending itself carries that function.

Yes, normally yes.

The sentence begins with a subordinate clause introduced by ako:

• Ako majstor ne zatvori tu rupu danas, ...

In standard writing, that clause is separated from the main clause by a comma:

• ..., sutra nećemo moći koristiti roletu.

So the comma is the normal and correct punctuation here.

In this sentence, ako clearly means if.

That is its main use:

• Ako dođe, javit ću ti. = If he comes, I’ll let you know.

Depending on style and context, Croatian may also use ukoliko in similar meanings, but ako is the everyday, common word.

So here:

• Ako majstor ne zatvori... = If the handyman doesn’t close...

Because both clauses are negative, but for different reasons:

1. Ako majstor ne zatvori...

   • the condition is negative:
   • if he doesn’t close it

2. sutra nećemo moći...

   • the result is also negative:
   • we won’t be able to...

So this is a natural negative condition + negative consequence structure:

• if X does not happen,
• then Y will not be possible.

Very literally:

• Ako = if
• majstor = the handyman / repairman
• ne zatvori = does not close
• tu rupu = that hole
• danas = today
• sutra = tomorrow
• nećemo moći = we will not be able
• koristiti = to use
• roletu = the shutter / blind

So a very literal gloss would be:

• If the handyman does not close that hole today, tomorrow we will not be able to use the shutter.

That literal structure matches the Croatian quite closely.