Čudo je da je predana prtljaga stigla.

They are the same word, but they do two different jobs.

• In Čudo je ..., je is the present tense of biti and works like the English is.
• In da je ... stigla, je is the auxiliary used to form the perfect tense.

So:

• Čudo je = It is a miracle / It’s surprising
• je stigla = has arrived / arrived

Croatian often uses the same form of biti both as a main linking verb and as a tense auxiliary.

It is a very common Croatian pattern for commenting on a situation.

Literally, čudo means miracle, wonder, or surprising thing.
So Čudo je da ... is literally something like:

• It is a miracle that ...
• It’s surprising that ...
• It’s amazing that ...

Grammatically, čudo is a noun, but the whole expression functions like an English comment clause.

Similar Croatian patterns are:

• Šteta je da ... = It’s a pity that ...
• Dobro je da ... = It’s good that ...
• Važno je da ... = It’s important that ...

Here da introduces a subordinate clause, much like English that.

So:

• Čudo je da je predana prtljaga stigla.
• It’s a miracle that the checked baggage arrived.

The clause after da gives the content of what is surprising.

In this sentence, da je predana prtljaga stigla is the idea being commented on by Čudo je.

In this context, predana prtljaga means checked baggage or checked luggage.

The word predana comes from predati, which means to hand over, submit, or in travel contexts check in. So predana prtljaga is luggage that has been handed over to the airline.

A useful contrast is:

• ručna prtljaga = hand luggage / carry-on
• predana prtljaga = checked baggage

So even though predana literally means handed over, in airport language it is a normal way to say checked.

Because prtljaga is a feminine singular noun.

Croatian words that describe or agree with a noun usually match it in:

• gender
• number
• often also case

So here:

• prtljaga = feminine singular
• predana = feminine singular
• stigla = feminine singular

Even though baggage may refer to several physical items, prtljaga is grammatically singular, just like English luggage or baggage.

Stigla is the l-participle of stići in the feminine singular form.

With the auxiliary je, it makes the perfect tense:

• je stigla = arrived / has arrived

Because the subject is prtljaga (feminine singular), the participle must also be feminine singular:

• stigao = masculine singular
• stigla = feminine singular
• stiglo = neuter singular
• stigli / stigle = plural forms

So stigla is chosen purely because it agrees with prtljaga.

Because stići is perfective, and this sentence is about a completed result: the baggage successfully arrived.

• stići = to arrive, to make it, to reach the destination
• stizati = imperfective, more like to be arriving, to arrive repeatedly, or focusing on the process/habit

Here the important fact is the completed event, so stigla is the natural choice.

If you used stizala, it would suggest repeated arrival or an ongoing process, which does not fit this sentence well.

Croatian word order is more flexible than English word order, but this version is natural and neutral.

A key point is that je is a clitic, and clitics usually come very early in the clause, often in the second position. After da, it is very common to get:

• da je ...

Then the subject predana prtljaga comes before the participle stigla, which is also a normal order.

Other word orders are possible, but they change emphasis:

• da je predana prtljaga stigla = neutral
• da je stigla predana prtljaga = more marked, with focus on arrived

So the sentence you have is a straightforward, standard ordering.

Yes, you can hear that, especially in more conversational or exclamatory speech.

• Čudo je da je predana prtljaga stigla. = fuller, more neutral
• Čudo da je predana prtljaga stigla. = slightly more colloquial or emotional

Both are understandable. The version with je is the safer choice for learners and the more formally complete structure.

Because in Croatian, a da-clause like this one is often not separated by a comma when it is tightly connected to the main clause.

This is similar to other common sentences such as:

• Drago mi je da si došao.
• Mislim da je u pravu.
• Šteta je da kasnimo.

So Čudo je da je predana prtljaga stigla. is correctly written without a comma.

Because Croatian does not have articles like English a and the.

So Croatian simply says:

• prtljaga

and the listener understands from context whether it means:

• baggage in general
• the baggage
• sometimes even a piece of baggage, depending on the situation

In this sentence, context would normally make it clear that we mean the relevant baggage already being talked about, so English often uses the even though Croatian does not.

Yes, predan/predana can mean devoted, dedicated, or committed when talking about people or attitudes.

For example:

• predana učiteljica = a devoted teacher

But in predana prtljaga, that meaning does not fit. With prtljaga, it clearly means handed over / checked in.

So the meaning of predan/predana depends heavily on context:

• with people: often devoted
• with documents, tasks, luggage, etc.: often submitted / handed over / checked