Územní platnost cestovního pojištění je důležitá.

A natural breakdown is:

• územní = territorial, geographical, relating to an area
• platnost = validity, applicability
• cestovního pojištění = of travel insurance
• je = is
• důležitá = important

So the sentence is literally something like:

• The territorial validity of travel insurance is important
• or more naturally, The geographical scope of travel insurance is important

In insurance language, územní platnost means the area where the insurance applies.

The subject is platnost.

More exactly:

• platnost = the main noun, so it is the grammatical subject
• územní describes platnost
• cestovního pojištění tells you validity of what? = of travel insurance
• je důležitá says something about that subject

So the structure is:

• [Územní platnost cestovního pojištění] = subject noun phrase
• [je důležitá] = predicate

Because it agrees with platnost, which is a feminine noun.

In Czech, predicate adjectives agree with the subject in gender and number.

• platnost is feminine singular
• therefore důležitý changes to důležitá for feminine singular

This agreement is with platnost, not with pojištění.

That is why the sentence has:

• platnost je důležitá

not

• platnost je důležité

Because platnost usually takes a genitive phrase when you say validity of something.

Here:

• platnost čeho? = validity of what?
• answer: cestovního pojištění = of travel insurance

So:

• pojištění is in the genitive singular
• cestovního matches pojištění in case, number, and gender

A useful pattern is:

• platnost smlouvy = validity of a contract
• platnost dokladu = validity of a document
• platnost pojištění = validity of insurance

Because for this noun, the nominative singular and genitive singular have the same form: pojištění.

So even though it is grammatically genitive here, the noun itself does not visibly change.

What does show the genitive clearly is the adjective:

• dictionary form: cestovní pojištění
• genitive singular: cestovního pojištění

That adjective ending -ho is your big clue.

Územní is a soft adjective. Soft adjectives often have -í in several forms, including nominative singular feminine.

So here:

• územní platnost = territorial validity

Even though platnost is feminine, územní stays územní.

Compare:

• územní platnost = feminine singular
• územní plán = masculine inanimate singular
• územní rozhodnutí = neuter singular

This is normal for adjectives of this type.

Yes, and this can be confusing.

The verb platit can mean:

• to pay
• and also to be valid / to apply

From that second meaning comes:

• platný = valid
• platnost = validity

So in this sentence, platnost is not about payment. It means validity or scope of applicability.

Yes, it is a very common formal expression, especially in:

• insurance
• law
• administration
• contracts
• transport tickets
• warranties

It means the geographical area where something is valid or effective.

For example:

• Územní platnost jízdenky = the geographical validity of a ticket
• Územní platnost pojištění = the territorial scope of insurance

So this is not a random combination of words; it is a standard phrase.

No, Czech word order is fairly flexible, but this version is the most neutral and straightforward.

Neutral statement:

• Územní platnost cestovního pojištění je důležitá.

Other possible orders can shift emphasis, for example:

• Důležitá je územní platnost cestovního pojištění.
• U cestovního pojištění je územní platnost důležitá.

These all can work in the right context, but the original sentence is the best basic version for a learner.

Normally, no. In a regular Czech sentence, you keep je.

So:

• Územní platnost cestovního pojištění je důležitá.

is standard.

You may sometimes see omission in:

• headlines
• notes
• very compressed style

But in normal full sentences, Czech does not usually drop the present tense of být the way some other Slavic languages do.

A rough English-friendly guide is:

OO-zem-nyee PLAT-nost TSES-tov-nyee-ho PO-yish-tyeh-nyee yeh DOO-leh-zhee-tah

A few pronunciation tips:

• Ú = long oo
• z = like English z
• c = ts
• j = y
• š = sh
• ž = the s in measure
• ť = a soft ty
• á and í are long vowels

Also, Czech stress is usually on the first syllable of each word:

• Územní
• PLATnost
• CEStovního
• POjištění
• JE
• DŮležitá

The dictionary form is:

• cestovní pojištění = travel insurance

In this sentence it changes because of grammar:

• dictionary form: cestovní pojištění
• after platnost: cestovního pojištění

So if you want to memorize it, learn both:

• cestovní pojištění = the basic term
• platnost cestovního pojištění = validity of travel insurance

That will help you recognize why the adjective changes.