Garderoba jest duża.

Because garderoba is a feminine singular noun, and Polish adjectives must agree with the noun in gender, number, and case.

So the adjective big changes like this in the singular:

• duży = masculine
• duża = feminine
• duże = neuter

Since garderoba is feminine, the correct form is duża.

Jest is the 3rd person singular present form of być, which means to be.

So:

• garderoba = wardrobe / closet / dressing room
• jest = is
• duża = big

In this sentence, jest works just like English is.

Here duża is in the nominative singular feminine, matching garderoba.

After być when the description is an adjective, Polish normally uses the nominative:

• Garderoba jest duża.

Not dużą.

Dużą is a different form, used in other grammatical contexts, such as the accusative or instrumental feminine singular.

A useful comparison:

• Jan jest miły. = John is nice. → adjective, so nominative
• Jan jest lekarzem. = John is a doctor. → noun, often instrumental

Yes. Garderoba is feminine.

A very common clue in Polish is that nouns ending in -a are often feminine, and garderoba follows that pattern.

That is why the adjective also has the feminine form duża.

Garderoba jest duża is the most neutral and natural order.

Polish word order is fairly flexible, because endings carry a lot of grammatical information. You can change the order for emphasis, for example:

• Duża jest garderoba.

That sounds more marked or stylistic, with extra focus on duża.

For a learner, Garderoba jest duża is the best standard version.

A rough pronunciation guide is:

• garderoba ≈ gar-de-RO-ba
• jest ≈ yest
• duża ≈ DU-zha

A few notes:

• Polish stress is usually on the second-to-last syllable, so gardeROba
• ż sounds roughly like the s in measure
• j in jest sounds like English y
• Polish r is usually tapped or lightly rolled

Because Polish does not use articles.

So garderoba can mean:

• the wardrobe
• a wardrobe
• the closet
• a closet

Which one sounds best depends on the context.

Yes. Depending on context, garderoba can mean things like:

• a wardrobe
• a dressing room
• a cloakroom
• a walk-in closet

So even if the grammar is straightforward, the best English translation can change with the situation.

In a normal full sentence like this, you should usually keep jest:

• Garderoba jest duża.

If you drop it, the result can sound incomplete, elliptical, or stylistically marked:

• Garderoba duża → not the normal standard sentence for a learner

So for standard Polish, use jest here.

You can change it very easily:

• Negative: Garderoba nie jest duża. = The wardrobe / closet is not big.
• Question: Czy garderoba jest duża? = Is the wardrobe / closet big?

The word nie makes the sentence negative, and czy is a common way to form a yes/no question.

Yes, if the context already makes it clear what you are talking about.

Polish often omits the subject when it is obvious. So:

• Jest duża. = It is big / She is big

But on its own, that is less clear than Garderoba jest duża, so the full version is better for learning and for clear standalone sentences.