Prtljag nije ni na traci za prtljag ni na aerodromu.

Ni ... ni means neither ... nor.

So:

• nije ni na traci za prtljag ni na aerodromu
• = is neither on the baggage carousel nor at the airport

In Serbian, ni ... ni is the normal way to connect two negative alternatives.

Yes, and that is normal in Serbian.

Serbian commonly uses negative concord, which means multiple negative elements appear together in the same sentence:

• nije = is not
• ni ... ni = neither ... nor

So Prtljag nije ni na traci za prtljag ni na aerodromu is the standard Serbian structure.

A literal breakdown is something like:

• Prtljag = luggage
• nije = is not
• ni ... ni = neither ... nor

English avoids stacking negatives this way, but Serbian does not.

The two instances of prtljag are doing different jobs.

1. Prtljag at the beginning is the subject:

   • The luggage

2. In traka za prtljag, the second prtljag is part of a noun phrase:

   • belt/carousel for luggage
   • so: baggage belt / baggage carousel

This repetition is completely natural. In English we also repeat the idea:

• The luggage is not on the luggage belt

Literally, it means belt for luggage.

Breakdown:

• traka = strip, belt, conveyor belt
• za = for
• prtljag = luggage

At an airport, traka za prtljag means the baggage conveyor/carousel where bags appear after a flight.

Because na here means on in the sense of location, and with that meaning it requires the locative case.

The basic noun is:

• traka = belt, conveyor

Its locative singular form is:

• traci

So:

• na traci = on the belt/carousel

This is a common pattern:

• na stolu = on the table
• na polici = on the shelf
• na traci = on the belt

Aerodromu is also in the locative singular.

The base form is:

• aerodrom = airport

After na when talking about location, Serbian uses the locative:

• na aerodromu = at the airport / on the airport grounds

So both places in the sentence are locative phrases:

• na traci
• na aerodromu

Because Serbian normally says na aerodromu for at the airport.

This is one of those place expressions that you mostly learn as a set phrase. Serbian often uses na with places or institutions where English might use at:

• na aerodromu = at the airport
• na fakultetu = at the faculty/college
• na poslu = at work

By contrast, u aerodromu would usually sound like inside the airport building, and that is not the normal phrasing here.

In Serbian, prtljag works like a collective or mass noun, similar to luggage in English.

So even if it refers to multiple bags, the noun itself is singular:

• Prtljag je stigao. = The luggage has arrived.
• Prtljag nije ovde. = The luggage isn’t here.

If you want to talk about individual bags, you would use a different noun, such as torbe or koferi, depending on what you mean.

Normally, no. The standard structure is:

• nije ni X ni Y

So this sentence naturally uses:

• nije ni na traci za prtljag ni na aerodromu

If you want a different structure, you could use niti:

• Prtljag nije na traci za prtljag niti na aerodromu.

That also means The luggage is neither on the baggage carousel nor at the airport.

The given word order is the most neutral and natural:

• Prtljag nije ni na traci za prtljag ni na aerodromu.

Serbian word order is fairly flexible, but changes in order often add emphasis or sound more literary or marked.

For example, you could move things around for emphasis, but the basic learner-friendly version is the one you have here.

So if you are learning, this is the safest pattern to copy:

• subject + negative verb + ni ... ni ...

Not exactly.

• traka za prtljag = the baggage belt/carousel itself
• baggage claim in English can mean the whole area, not just the belt

So in this sentence, Serbian is specifically talking about the carousel/belt where luggage comes out.

If you wanted to talk about the whole baggage-claim area, Serbian might use a different expression depending on context.