Potpisana izjava je sada potpuna.

Because it agrees with izjava, which is a feminine singular noun in the nominative case.

• izjava = feminine singular nominative
• so the adjective/participle modifying it must match:
  • potpisan (masculine)
  • potpisana (feminine)
  • potpisano (neuter)

So potpisana izjava means signed statement/declaration, with both words matching grammatically.

It is a past passive participle used like an adjective.

It comes from the verb potpisati = to sign.
The participle potpisan / potpisana / potpisano means signed.

In this sentence, it behaves just like an adjective because it describes the noun izjava:

• potpisana izjava = a signed statement

This is very common in Croatian:

• zatvorena vrata = closed door(s)
• napisano pismo = written letter

Because it is a predicate adjective and it also agrees with the subject, potpisana izjava.

In Croatian, after biti (to be), adjectives still match the subject in gender and number:

• Izjava je potpuna. = The statement is complete.
• Dokument je potpun. = The document is complete.
  (dokument is masculine)
• Pismo je potpuno. = The letter is complete.
  (pismo is neuter)

So potpuna is feminine singular because izjava is feminine singular.

Je is the 3rd person singular present form of biti (to be).

So it means is:

• izjava je potpuna = the statement is complete

Unlike in some languages where the present form of to be can be omitted, in standard Croatian it is normally expressed here. So je is necessary in this sentence.

Here is the breakdown:

• potpisana — nominative feminine singular
• izjava — nominative feminine singular
• je — verb, not a case form
• sada — adverb
• potpuna — nominative feminine singular

Why nominative? Because potpisana izjava is the subject of the sentence, and potpuna is a predicate adjective agreeing with that subject.

Yes, Croatian word order is fairly flexible.

Potpisana izjava je sada potpuna. is natural and emphasizes the idea that now the statement is complete.

Other possible orders include:

• Potpisana izjava sada je potpuna.
• Izjava je sada potpuna.
• Sada je potpisana izjava potpuna.
  This is possible, but it sounds more marked or context-dependent.

Croatian often moves words around for emphasis, topic, or rhythm. The meaning usually stays similar, but the focus can shift.

Izjava can mean several related things depending on context, including:

• statement
• declaration
• formal statement
• sometimes testimony or announcement, depending on the situation

So the exact English word depends on context. In legal or administrative language, izjava often means a formal declaration or signed statement.

Croatian has no articles like English the and a/an.

So potpisana izjava can mean:

• a signed statement
• the signed statement

The context tells you which one is meant.

That is why one Croatian sentence can correspond to more than one natural English translation.

Yes. That would still be grammatical:

• Izjava je sada potpuna. = The statement is now complete.

The difference is that without potpisana, you are no longer specifying that it is the signed statement. The original sentence highlights that the statement has been signed and, as a result or in that state, is now complete.

Yes, potpun / potpuna / potpuno is a very common word for complete, full, or entire, depending on context.

In this sentence, potpuna means something like:

• complete
• fully complete
• not missing anything

In administrative or formal contexts, this often suggests that all required parts are present, so the signed statement is now complete in the sense of being properly finished.

Yes, it sounds fairly neutral-to-formal, especially because of the words izjava and potpuna.

It would fit well in:

• legal contexts
• official documents
• administrative communication
• formal notices

It is not unnatural in everyday Croatian, but it feels more like something you might read or hear in a formal setting than in casual conversation.