Příplatek za roaming je vysoký.

Příplatek means an extra charge, surcharge, or additional fee — something you pay on top of the normal price.

So in this sentence, příplatek za roaming is specifically an added fee for roaming, not just the general bill.

Related words:

• poplatek = a fee, charge
• cena = price
• platba = payment
• příplatek = extra fee / surcharge

Here za means for in the sense of charged for something.

So:

• příplatek za roaming = surcharge for roaming
• platit za něco = to pay for something

This is a very common pattern in Czech:

• poplatek za parkování = parking fee
• pokuta za rychlost = fine for speeding
• peníze za lístek = money for the ticket

In this sentence, za takes the accusative.

So the structure is:

• příplatek za + accusative

With many nouns, the accusative form may look different. Here, however, roaming is a borrowed masculine inanimate noun, and its accusative is the same as its nominative:

• nominative: roaming
• accusative: roaming

That is why you see za roaming, not a visibly changed form.

Yes, roaming is a borrowed word used in Czech, especially in telecom contexts.

Many borrowed nouns in Czech either:

• decline only a little,
• or in some contexts look unchanged.

Here roaming behaves like a masculine inanimate noun, and in the accusative singular it looks the same as the basic dictionary form.

So za roaming is normal Czech usage.

Because vysoký agrees with příplatek.

Příplatek is:

• masculine
• singular
• nominative

So the adjective must match:

• vysoký příplatek = a high surcharge

Compare:

• cena je vysoká = the price is high
  (cena is feminine)
• nájemné je vysoké = the rent is high
  (nájemné is neuter)

Yes. Czech word order is more flexible than English word order.

The basic sentence here is:

• Příplatek za roaming je vysoký.

This is a neutral, natural order:

• subject: Příplatek za roaming
• verb: je
• adjective/predicate: vysoký

You could also hear:

• Za roaming je příplatek vysoký.
• Vysoký je příplatek za roaming.

But those versions change the emphasis. The original sentence is the most straightforward.

Je is the 3rd person singular of být = to be.

So:

• je = is

The sentence structure is:

• Příplatek za roaming = the roaming surcharge
• je = is
• vysoký = high

Unlike in some languages, Czech usually keeps the verb to be in the present tense in this kind of sentence.

Czech has no articles.

So příplatek can mean:

• a surcharge
• the surcharge

Which one is meant depends on context.

In this sentence, English might translate it as:

• The roaming surcharge is high or
• A roaming surcharge is high

Usually, context tells you which sounds best.

Yes. Czech often uses vysoký literally meaning high for things like prices, costs, fees, and numbers.

Very natural examples:

• vysoká cena = a high price
• vysoký poplatek = a high fee
• vysoké náklady = high costs

So Příplatek za roaming je vysoký sounds completely natural.

A rough pronunciation guide:

• Příplatek ≈ pzhee-pla-tek
• za ≈ za
• roaming ≈ rou-ming
• je ≈ ye
• vysoký ≈ vi-soh-kee

A few helpful points:

• ř in pří- is a special Czech sound, difficult for English speakers. Approximate it at first with something like rzh or zh.
• í and ý are long vowels.
• Czech stress is usually on the first syllable of each word:
  • PŘÍ-pla-tek
  • ROA-ming
  • VY-so-ký

Yes, you can, and it would also be natural.

The difference is small:

• příplatek = extra charge / surcharge
• poplatek = fee / charge more generally

So:

• Příplatek za roaming je vysoký emphasizes that roaming costs extra.
• Poplatek za roaming je vysoký is more like the fee for roaming is high.

Which one is better depends on the exact context.

It is definitely about the surcharge/extra fee, not about roaming itself.

The grammatical subject is:

• Příplatek za roaming = the roaming surcharge

And vysoký describes příplatek.

So the meaning is:

• the extra charge is high not
• roaming is high

That is why understanding the noun phrase příplatek za roaming as one unit is important.