Bilo da je početni, bilo da je napredni, kurs je važan.

It is a correlative structure meaning whether ... or ....

So:

• Bilo da je početni, bilo da je napredni
  = Whether it is beginner-level or advanced

This pattern is very common in Serbian when you want to present two alternatives, while saying that the main statement is true in either case.

Because Serbian normally uses the full pair:

• bilo da ... bilo da ...

This is similar to English whether ... or .... The repetition helps clearly mark both alternatives.

So the structure is:

• bilo da je X, bilo da je Y, ...

You should think of it as one fixed pattern, not as an accidental repetition.

Here bilo is part of the fixed conjunction-like expression bilo da.

Historically, bilo is related to the verb biti (to be), but in this construction learners usually do best to treat bilo da as a set phrase meaning whether.

So in this sentence, it is better not to analyze bilo as an independent verb with its own literal meaning. It mainly helps form the pattern whether ... or ....

Because the structure is:

• bilo da + clause

And the clause here is:

• je početni
• je napredni

So:

• bilo da je početni = whether it is beginner-level
• bilo da je napredni = whether it is advanced

The word da introduces a subordinate clause, and je is the present tense of biti (to be), here meaning is.

The subject is understood from the context. It is not repeated, because Serbian often leaves it implicit when it is obvious.

In this sentence, the understood subject is something like:

• kurs = the course
• or possibly on / it, depending on the broader context

So the meaning is essentially:

• whether the course is beginner-level or advanced

Even though kurs appears later in the sentence, it is understood as the thing being described by početni and napredni.

Because Serbian often allows adjectives to stand on their own when the noun is clear from context.

Here:

• početni = beginner-level / introductory
• napredni = advanced

The noun they describe is understood, most likely kurs.

So instead of saying the fuller version:

• Bilo da je početni kurs, bilo da je napredni kurs...

Serbian can shorten it to:

• Bilo da je početni, bilo da je napredni...

This is natural when the omitted noun is obvious.

Yes, it would be grammatically correct, but it sounds more repetitive.

Serbian often prefers the shorter version when the noun is easy to understand:

• Bilo da je početni, bilo da je napredni, kurs je važan.

The full version is possible, but the shortened version is more elegant and natural in many contexts.

They are in the nominative masculine singular form.

That is because they function as predicate adjectives after je:

• kurs je početni
• kurs je napredni

Since kurs is masculine singular, the adjective agrees with it:

• početni
• napredni
• važan

If the noun were feminine, the forms would change:

• škola je početna / napredna / važna

Because važan agrees with kurs.

• kurs is masculine singular
• so the adjective must also be masculine singular:
  • važan

Compare:

• kurs je važan — masculine
• lekcija je važna — feminine
• predavanje je važno — neuter

Because the main clause comes after the subordinate alternatives.

Structure:

• Bilo da je početni, bilo da je napredni = subordinate part
• kurs je važan = main clause

Even though kurs is understood earlier, it still needs to appear in the main clause because that is the actual statement being made:

• the course is important

So the sentence means: regardless of which type it is, the course is important.

The basic pattern is quite stable, but Serbian does allow some flexibility.

The most natural version is:

• Bilo da je početni, bilo da je napredni, kurs je važan.

You could also move the main clause forward in some contexts, for example:

• Kurs je važan, bilo da je početni, bilo da je napredni.

That also sounds natural and may even sound more straightforward to some speakers.

So the word order is not absolutely fixed, but the internal structure bilo da ... bilo da ... should stay intact.

You could, but that sounds more literary or formal in modern English.

The most natural English equivalent is:

• Whether it is beginner-level or advanced, the course is important.

A somewhat closer but still natural English version is:

• Whether it is introductory or advanced, the course is important.

So for learning purposes, whether ... or ... is the best match.

The commas separate the subordinate bilo da clauses from each other and from the main clause.

So the structure is visually marked like this:

• Bilo da je početni,
• bilo da je napredni,
• kurs je važan.

This punctuation helps the reader see the contrastive alternatives before reaching the main point.

Yes, but more precisely it means beginner-level, elementary, or introductory, depending on context.

So:

• početni kurs = beginner course / introductory course
• napredni kurs = advanced course

English often uses a noun-like adjective such as beginner, but Serbian is using a regular adjective here.

Yes, there can be a difference.

• početni usually means initial, elementary, introductory, or beginner-level
• početnički means more literally for beginners or characteristic of a beginner

For courses, početni kurs is very natural for beginner course.
Početnički kurs can also occur, but početni is often the more neutral and standard label for levels.

So in this sentence, početni fits very well.

In this exact pattern, it is most natural to keep the full parallel structure:

• bilo da je početni, bilo da je napredni

Dropping da je in the second half would usually sound less balanced or less standard in this kind of sentence.

Serbian often likes symmetry in paired constructions, so repeating the whole pattern is preferred.

It sounds mostly neutral to slightly formal.

The structure bilo da ... bilo da ... is common in both writing and careful speech. It is not overly literary, but it is a bit more structured than very casual everyday phrasing.

In very casual speech, someone might choose a simpler wording, but this sentence is perfectly normal and natural Serbian.

Sometimes Serbian can use ili in similar meanings, but here the standard and best structure is:

• bilo da ... bilo da ...

Using ili would change the feel of the sentence and would not match the neat correlative construction as well.

So for this sentence, learners should remember:

• bilo da X, bilo da Y = whether X or Y

That is the most useful pattern to learn.

A simple breakdown is:

• Bilo da je početni = whether it is beginner-level
• bilo da je napredni = whether it is advanced
• kurs je važan = the course is important

So the whole sentence follows this logic:

• No matter which of the two it is, the course is important.

That is the core idea of the grammar here.