Politické rozhodnutí je důležité.

Because they both agree with rozhodnutí, which is a neuter singular noun.

In Czech, adjectives change their endings to match the noun in:

• gender
• number
• case

Here, rozhodnutí is:

• neuter
• singular
• nominative

So both adjectives take the neuter singular nominative ending -é:

• politické rozhodnutí = political decision
• rozhodnutí je důležité = the decision is important

Rozhodnutí is neuter.

A useful clue is that many Czech nouns ending in -í are neuter, especially verbal nouns like:

• rozhodnutí = decision
• stavení = building
• učení = learning

You still need to learn nouns individually, but -í is often a strong sign of neuter gender.

Czech does not use articles like English the and a/an.

So:

• politické rozhodnutí can mean a political decision or the political decision
• the exact meaning depends on context

In your sentence, the English translation might be:

• A political decision is important
• The political decision is important
• Political decision-making is important only in some contexts, though that is less direct here

Usually the surrounding context tells you which one is meant.

Je is the 3rd person singular present tense of the verb být (to be).

So:

• já jsem = I am
• ty jsi = you are
• on / ona / ono je = he / she / it is

In this sentence:

• Politické rozhodnutí je důležité
• literally: Political decision is important

So je simply means is.

It is in the nominative case.

That is because rozhodnutí is the subject of the sentence:

• Politické rozhodnutí = the political decision
• je důležité = is important

In Czech, the subject is typically in the nominative. Predicate adjectives like důležité also match the subject in gender and number.

Yes. It is a very standard Czech structure:

• politické = adjective (political)
• rozhodnutí = noun (decision)

The adjective comes before the noun, just like in English.

Because Czech has agreement, the adjective changes form to fit the noun:

• politický problém = political problem (masculine)
• politická strana = political party (feminine)
• politické rozhodnutí = political decision (neuter)

In Czech, důležité here is an adjective, not an adverb.

It describes the noun rozhodnutí, even though it comes after je:

• rozhodnutí je důležité = the decision is important

Czech predicate adjectives still agree with the subject:

• problém je důležitý = the problem is important
• situace je důležitá = the situation is important
• rozhodnutí je důležité = the decision is important

An adverb would describe a verb, not a noun.

Yes. Czech word order is more flexible than English because endings show the grammatical relationships.

The neutral order here is:

• Politické rozhodnutí je důležité.

But you could also say:

• Důležité je politické rozhodnutí.

That changes the emphasis, not the basic meaning. The second version sounds more like:

• What is important is the political decision or
• The political decision is what is important

So word order in Czech often affects focus and emphasis more than basic grammar.

A rough guide:

• rozhodnutí ≈ roz-hod-noo-tee
• důležité ≈ doo-leh-zhee-teh

A few pronunciation notes:

• ž sounds like the s in measure
• ů is pronounced like a long oo
• í and é are long vowels
• Czech stress is usually on the first syllable:
  • ROZhodnutí
  • DŮležité

Even though the stress is on the first syllable, long vowels still stay long.

Yes. It comes from the verb rozhodnout (se), meaning to decide.

So:

• rozhodnout = to decide
• rozhodnutí = decision

This is very common in Czech: a noun is formed from a verb and expresses the result or act of that verb.

For an English speaker, it helps to think of:

• decide → decision
• rozhodnout → rozhodnutí

Not exactly, because this sentence is clearly singular.

• rozhodnutí here is singular
• je means is, not are
• důležité agrees with a singular neuter noun

If you wanted Political decisions are important, Czech would normally use the plural:

• Politická rozhodnutí jsou důležitá.

So your original sentence means A/The political decision is important, not Political decisions are important.