Ako budeš dugo na bolovanju, moraš obavijestiti šeficu.

Because after ako when you are talking about a real possibility in the future, Croatian often uses budem / budeš / bude... with the verb biti.

So Ako budeš dugo na bolovanju means something like If you end up being on sick leave for a long time or simply If you are on sick leave for a long time with future meaning.

If you said Ako si dugo na bolovanju, that would usually sound more like a present situation, not the standard future-looking pattern used here.

No. It is not the conditional.

The Croatian conditional uses bih, bi, bismo, biste, bi.

Here, budeš is a future-related form of biti used in subordinate clauses such as clauses with ako, kad, čim, and similar time/condition words.

So this sentence is not hypothetical in the English would sense. It is a real future condition: if this happens, then you must do that.

In Croatian, the present tense is often used for general rules, obligations, and instructions, even when they apply to the future.

So moraš obavijestiti šeficu means you must notify your boss or you will have to notify your boss.

Using the present here sounds completely natural. It expresses obligation, not present-time action.

It is a set expression.

Biti na bolovanju means to be on sick leave.

Literally, na often means on, and bolovanje is sick leave. So the phrase works much like English to be on leave or to be on sick leave.

You should learn na bolovanju as a chunk, because that is the normal way to say it.

Bolovanju is in the locative singular.

That is because na takes the locative when it expresses location or a state of being somewhere, and here it means being on sick leave, not movement toward it.

So:

• na bolovanju = on sick leave, in the state of sick leave

The noun is bolovanje, a neuter noun, and its locative singular form is bolovanju.

Because šeficu is the accusative singular form, and it is the direct object of obavijestiti.

The basic form is šefica = female boss. But after a verb like obavijestiti when she is the person being informed, you need the accusative:

• šefica = nominative
• šeficu = accusative

This is a very common pattern for feminine nouns ending in -a:

• žena → ženu
• sestra → sestru
• šefica → šeficu

Because after the modal verb morati, Croatian normally uses the infinitive.

So:

• moraš obavijestiti = you must notify

This is similar to English must notify.

You do not need another conjugated verb here. The only conjugated verb in that part is moraš.

This is about aspect.

Obavijestiti is perfective. It means to inform someone as a completed action, usually once.

That fits this sentence well, because the idea is that you need to perform one complete action: notify your boss.

Obavještavati is imperfective. It suggests repeated, ongoing, or habitual informing.

So here:

• obavijestiti šeficu = notify the boss
• obavještavati šeficu = be informing / keep informing the boss

The perfective form is the natural choice in this sentence.

Yes, very often.

Javiti šefici is common and slightly more everyday in tone. Obavijestiti šeficu sounds a bit more formal or official.

Both can work, but obavijestiti is a good standard verb for inform / notify.

Also notice the case pattern changes a little:

• obavijestiti šeficu → direct object in accusative
• javiti šefici → indirect object in dative

So both are possible, but the grammar is not identical.

Dugo is an adverb meaning for a long time or long in the sense of duration.

It modifies the idea of being on sick leave:

• biti dugo na bolovanju = to be on sick leave for a long time

It does not change form here. As an adverb, it stays dugo.

Croatian usually leaves out subject pronouns when they are already clear from the verb ending.

Here:

• budeš already means you are / you will be
• moraš already means you must

So ti is unnecessary unless you want emphasis or contrast.

For example:

• Ako budeš dugo na bolovanju, moraš obavijestiti šeficu. = neutral
• Ako budeš dugo na bolovanju, ti moraš obavijestiti šeficu. = more emphatic, like you must notify her

Not completely. Croatian word order is fairly flexible.

This sentence starts with the if-clause:

• Ako budeš dugo na bolovanju, moraš obavijestiti šeficu.

That is a very natural order because it presents the condition first and the result second.

You could also say:

• Moraš obavijestiti šeficu ako budeš dugo na bolovanju.

That is also correct. The meaning stays basically the same, though the focus is a little different.

Because the sentence begins with a subordinate clause introduced by ako.

So the structure is:

• Ako budeš dugo na bolovanju = subordinate conditional clause
• moraš obavijestiti šeficu = main clause

When the subordinate clause comes first, Croatian normally separates it from the main clause with a comma.