Premiéra je zítra.

Premiéra is a feminine singular noun in the nominative case here, because it is the subject of the sentence.

So the structure is basically:

• Premiéra = the premiere
• je = is
• zítra = tomorrow

In this sentence, premiéra is just the dictionary form of the noun.

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

So:

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

In Premiéra je zítra, je means is.

English and Czech work similarly here:

• The premiere is tomorrow.
• Premiéra je zítra.

Because zítra is an adverb, not a noun.

It simply means tomorrow, so Czech uses it directly without a preposition in this kind of sentence:

• Je to zítra. = It is tomorrow.
• Odjíždíme zítra. = We are leaving tomorrow.

You do not say v zítra in standard Czech.

Yes. Zítra je premiéra is perfectly natural.

Czech word order is more flexible than English, so both of these work:

• Premiéra je zítra.
• Zítra je premiéra.

The difference is mainly emphasis:

• Premiéra je zítra. → focuses a bit more on the premiere
• Zítra je premiéra. → focuses a bit more on tomorrow

Both are normal.

In a normal full sentence, no. You usually need je here.

So standard Czech is:

• Premiéra je zítra.

If you say only:

• Premiéra zítra

that sounds more like a headline, note, schedule entry, or informal shorthand, not a complete neutral sentence.

A helpful approximation is:

• Premiéra ≈ PREM-yeh-raa
• je ≈ ye
• zítra ≈ ZEE-tra

A few useful points:

• Czech stress is usually on the first syllable of each word.
• j in Czech is pronounced like English y in yes.
• í is a long ee sound.

So je is not like English jee; it is more like ye.

The accent mark in Czech usually shows that the vowel is longer.

So:

• í = a long ee sound
• á = a long aa sound

That is why:

• premiéra has a long é and á
• zítra has a long í

These length differences matter in Czech pronunciation and can sometimes distinguish words.

Czech has no articles like English a / an / the.

So Premiéra je zítra can mean:

• The premiere is tomorrow
• or sometimes just A premiere is tomorrow

In real context, it will usually be understood as the premiere.

Czech relies on context instead of articles.

Not very much in this exact sentence, because the verb je is the same regardless of gender in the present tense.

But the gender does matter elsewhere, for example with adjectives and past tense:

• Česká premiéra = Czech premiere
• Premiéra byla úspěšná. = The premiere was successful.

Here úspěšná is feminine because premiéra is feminine.

So gender is important, even if this sentence does not show much of it.

Yes, learners sometimes notice the similarity.

• premiéra = premiere
• premiér = prime minister

They are different words:

• Premiéra je zítra. = The premiere is tomorrow.
• Premiér je v Praze. = The prime minister is in Prague.

So the final -a matters a lot here.