Truhla je zavřená.

Because truhla is a feminine singular noun in Czech.

The adjective zavřený / zavřená / zavřené has to agree with the noun it describes in:

• gender
• number
• usually also case

So here:

• truhla = feminine singular
• therefore zavřená = feminine singular

Compare:

• hrad je zavřený = the castle is closed (masculine)
• truhla je zavřená = the chest is closed (feminine)
• okno je zavřené = the window is closed (neuter)

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

So the sentence is built like this:

• truhla = chest
• je = is
• zavřená = closed

Literally: The chest is closed.

In Czech, this kind of sentence normally uses být just like English does.

In normal standard Czech, no. You usually keep je in the present tense.

So:

• Truhla je zavřená. = correct
• Truhla zavřená. = not normal as a full neutral sentence

You might hear omitted forms in headlines, notes, very informal speech, or poetic style, but learners should use je here.

For learners, the simplest and most useful way to think of it is: it behaves like an adjective here.

It comes from the verb zavřít = to close, but in this sentence zavřená describes the state of the chest:

• the chest is closed

So it works much like an adjective such as:

• velká = big
• stará = old
• těžká = heavy

In practice, zavřená here means closed/shut, describing the result or condition.

It is in the nominative singular.

That is because truhla is the subject of the sentence:

• Truhla je zavřená.
• The chest is closed.

Dictionary form:

• truhla = nominative singular

Because the sentence is just subject + is + adjective, the subject stays in the nominative.

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

So truhla can mean:

• a chest
• the chest

Which one is meant depends on context.

That is very normal in Czech. You do not need to add anything to express the.

A rough English-friendly guide:

• truhla ≈ TROO-hla
• je ≈ ye
• zavřená ≈ ZA-vrzhe-naa or ZA-vzhe-naa, depending on how well you can do ř

A few notes:

• j in Czech is like English y
• ch is not like English ch in chair; it is a throaty sound, like German Bach
• ř is a famous Czech sound, something like a mix of r and zh

If ř is difficult, that is completely normal. Learners often approximate it at first.

In Czech, stress normally falls on the first syllable of each word.

So:

• TRUH-la
• je
• ZA-vře-ná

This is much more regular than in English, which is good news for learners.

Yes, Czech word order is more flexible than English, but the meaning and emphasis can change.

Neutral order:

• Truhla je zavřená. = The chest is closed.

Other possible orders:

• Zavřená je truhla.
• Je zavřená truhla.

These are possible in certain contexts, but they sound more marked or stylistic. For a basic, neutral sentence, Truhla je zavřená is the best choice.

The opposite is otevřená = open.

So:

• Truhla je zavřená. = The chest is closed.
• Truhla je otevřená. = The chest is open.

This is a very useful pair:

• zavřený / zavřená / zavřené = closed
• otevřený / otevřená / otevřené = open

Truhla means a chest, trunk, or large box, often something wooden or old-fashioned.

It is a normal Czech noun, but it may sound a bit more specific than a general word like box. Depending on context, it can suggest:

• a storage chest
• a treasure chest
• an old trunk

It is grammatically feminine, which is why you get:

• ta truhla
• truhla je zavřená

You change both the noun and the adjective so they agree.

Singular:

• Truhla je zavřená. = The chest is closed.

Plural:

• Truhly jsou zavřené. = The chests are closed.

Changes:

• truhla → truhly
• je → jsou
• zavřená → zavřené

That agreement pattern is very important in Czech.

Usually zavřená means closed/shut, not specifically locked.

If you want to say locked, Czech often uses:

• zamčená

So:

• Truhla je zavřená. = The chest is closed.
• Truhla je zamčená. = The chest is locked.

A chest can be zavřená without being zamčená.