Polaznik polaže završni ispit.

Not exactly.

Polaznik means someone who attends a course, training, or program—so words like participant, attendee, trainee, or sometimes learner fit well.

It is not always the same as student:

• student in Serbian usually means a university student
• učenik usually means a school pupil
• polaznik is often someone enrolled in a course or training program

So polaznik is a very natural choice if the context is a course, workshop, language class, or training.

Polaže is the 3rd person singular present tense form of the verb polagati.

So:

• ja polažem = I am taking / I take
• ti polažeš = you are taking
• on/ona polaže = he/she is taking

In this sentence, polaznik polaže... means the participant is taking...

With ispit (exam), the verb polagati is very commonly used for taking/sitting an exam.

Usually, polagati ispit means to take / sit an exam.

This is an important distinction:

• polagati ispit = to be taking an exam / to sit an exam
• položiti ispit = to pass an exam

So:

• Polaznik polaže završni ispit. = The participant is taking the final exam.
• Polaznik je položio završni ispit. = The participant passed the final exam.

This is a very common aspect pair in Serbian:

• polagati = imperfective
• položiti = perfective

Polaznik is in the nominative singular, because it is the subject of the sentence.

It is the person doing the action:

• Polaznik = the participant
• polaže = is taking
• završni ispit = the final exam

So the structure is basically: subject + verb + object

It is in the accusative singular, because it is the direct object of polaže.

The participant is taking what? → završni ispit

A useful detail:

• ispit is a masculine inanimate noun
• for masculine inanimate nouns, accusative singular looks the same as nominative singular

So:

• nominative: završni ispit
• accusative: završni ispit

That is why it looks unchanged.

Because here the phrase is the direct object of the verb, and with a masculine inanimate noun like ispit, the accusative singular is the same as the nominative.

So:

• završni ispit = nominative / accusative singular
• završnog ispita would be genitive singular

You would use završnog ispita in other structures, for example:

• bez završnog ispita = without the final exam
• rezultat završnog ispita = the result of the final exam

In Serbian, adjectives normally come before the noun they describe, just like in English.

So:

• završni ispit = final exam
• težak ispit = difficult exam
• usmeni ispit = oral exam

The adjective must also agree with the noun in:

• gender
• number
• case

Here:

• ispit is masculine singular
• so the adjective is also masculine singular: završni

Because Serbian does not have articles like a and the.

So polaznik can mean:

• a participant
• the participant

And završni ispit can mean:

• a final exam
• the final exam

Which one sounds best in English depends on context. Serbian leaves that to context much more than English does.

Yes, you could. Serbian word order is more flexible than English word order.

The neutral, most straightforward order is:

• Polaznik polaže završni ispit.

But other orders are possible for emphasis:

• Završni ispit polaže polaznik.
• Polaže polaznik završni ispit.

These can sound more marked or stylistically different, depending on context.

So the original sentence is the most neutral subject–verb–object order, but Serbian is not as rigid as English.

Yes, polaže is present tense.

In Serbian, the present tense often covers both:

• a simple present idea
• a present progressive idea

So polaže can mean:

• takes
• is taking

In practice, English usually chooses the more natural option based on context. With an exam, is taking is often the most natural translation if we mean the action is happening now.

A rough English-friendly guide:

• Polaznik ≈ po-LAZ-nik
• polaže ≈ po-LA-zhe
• završni ≈ za-VRSH-nee
• ispit ≈ EES-peet

A few sound notes:

• ž sounds like the s in measure
• š sounds like sh
• r in završni is trilled or tapped
• i is usually like ee in see, but shorter

Yes, it is very normal and common.

• završni = final, concluding
• ispit = exam

So završni ispit is the standard phrase for final exam.

Depending on context, you might also hear:

• finalni ispit in some settings, but završni ispit is generally the more standard and idiomatic choice in Serbian

Only if the context really is a university student.

For example:

• Student polaže završni ispit. = The university student is taking the final exam.

But if the person is attending a course, training, seminar, or language program, polaznik is often better.

So the choice depends on who the person is:

• polaznik = course attendee / participant
• student = university student
• učenik = school pupil

The pattern is:

Polaznik + polaže + završni ispit
subject + verb + direct object

More specifically:

• Polaznik = nominative singular subject
• polaže = 3rd person singular present
• završni ispit = accusative singular object

So it is a very useful model sentence for building other Serbian sentences:

• Polaznik sluša predavanje. = The participant is listening to a lecture.
• Student piše test. = The student is writing a test.
• Učenik rešava zadatak. = The pupil is solving a task.