Bibliotekar će potvrditi razduženje.

This is the future I tense in Serbian.

It is built with:

• the clitic form of hteti (ću, ćeš, će, ćemo, ćete, će)
• plus the infinitive of the main verb

So here:

• će = will
• potvrditi = infinitive to confirm

Together, će potvrditi = will confirm.

With bibliotekar:

• Bibliotekar će potvrditi = The librarian will confirm

Because će is a clitic in Serbian. Clitics usually go in the second position of the sentence or clause.

So Serbian naturally puts it like this:

• Bibliotekar će potvrditi razduženje.

Not usually:

• Će bibliotekar potvrditi razduženje. ← unnatural in normal declarative speech

This “second-position” rule is very important in Serbian word order.

Because in this future construction, the auxiliary će carries the tense, and the main verb stays in the infinitive.

So:

• će potvrditi = will confirm

This is different from English, where only will changes and the main verb stays in the base form. In Serbian, that base-like form is the infinitive.

You may also hear another future pattern in Serbian, especially in speech:

• Bibliotekar će da potvrdi razduženje.

That also means The librarian will confirm the return/discharge.
But će potvrditi is very standard and common.

This is about verbal aspect, which is very important in Serbian.

• potvrditi = perfective
• potvrđivati = imperfective

Here, potvrditi is used because the sentence refers to a single completed action in the future: the librarian will confirm it, and that action will be completed.

So:

• će potvrditi = will confirm / will complete the confirmation
• će potvrđivati would suggest an ongoing, repeated, or process-like action, which does not fit as well here

In short, potvrditi is the natural choice for one finished future event.

It is the direct object, so it is in the accusative case.
But for some nouns, the accusative looks exactly like the nominative.

Razduženje is a neuter singular noun ending in -nje, and for this type of noun:

• nominative singular: razduženje
• accusative singular: razduženje

So the case is correct; it just doesn’t look different.

Razduženje is a neuter noun.

You can recognize that from the ending -e in the singular:

• to razduženje

It is also a verbal noun, built from a verb and referring to an action or process. Nouns in -nje often work this way in Serbian.

So even if you already know the meaning, it helps to notice that grammatically it behaves like a regular neuter noun.

Because Serbian has no articles.

English distinguishes:

• a librarian
• the librarian

Serbian usually just says:

• bibliotekar

The exact meaning depends on context. In a given situation, bibliotekar can mean:

• a librarian
• the librarian

The same is true for razduženje: Serbian does not use a/the there either.

Grammatically, bibliotekar is masculine singular.

It most directly refers to:

• a male librarian

If you want to specify a female librarian, Serbian usually uses:

• bibliotekarka

So:

• Bibliotekarka će potvrditi razduženje. = The female librarian will confirm the discharge/return.

That said, in some contexts masculine forms can be used more generically, but the basic form bibliotekar is masculine.

Yes, Serbian word order is fairly flexible, but the neutral version here is:

• Bibliotekar će potvrditi razduženje.

Other orders are possible for emphasis, for example:

• Razduženje će potvrditi bibliotekar.
  → emphasizes razduženje or contrasts who will confirm it

But remember: the clitic će still tends to stay in second position.

So word order can shift, but not completely freely.

Yes, in Serbian future tense you may also see forms where the auxiliary attaches to the verb:

• Bibliotekar potvrdiće razduženje.

However, that version is much less natural in this sentence with the subject first.
The most normal wording is:

• Bibliotekar će potvrditi razduženje.

You are more likely to see the attached form in sentences where the infinitive comes first, for example:

• Potvrdiće razduženje. = He/She will confirm the discharge/return.

So for learners, the safest model here is the original sentence with će after the first element.

You need to change both the subject and the future auxiliary.

Singular:

• Bibliotekar će potvrditi razduženje.
  = The librarian will confirm the discharge/return.

Plural:

• Bibliotekari će potvrditi razduženje.
  = The librarians will confirm the discharge/return.

Notice:

• bibliotekar → bibliotekari
• će stays će for both he/she/it and they

So the verb phrase does not change, but the noun does.