Learn Hardcore Czech: V našem městě je nové muzeum, které má velkou sbírku umění. - In our city there is a new museum which has a large collection of art.

The preposition v (in) normally requires the locative when it means a static location (where something is).
město (city/town) in the locative singular is městě.
náš (our) must agree with město in gender, number, and case, so you get:
- nominative: naše město
- locative: v našem městě

So v + locative answers the question kde? (where?): Where is the museum? → In our town → v našem městě.

Why is it našem městě and not naše město?

naše město is nominative (used for the subject), but here the phrase is governed by the preposition v, which requires the locative case for a location.

nominative: naše město – our town (as the subject)
locative: v našem městě – in our town

So the adjective náš changes to našem, and město changes to městě to show they are in the locative.

Why is there a comma before které?

In Czech, relative clauses (clauses beginning with který, která, které = which/that) are always separated from the main clause with a comma.

Main clause: V našem městě je nové muzeum (There is a new museum in our town)
Relative clause: které má velkou sbírku umění (which has a large collection of art)

Because které má velkou sbírku umění further describes muzeum, it is a relative clause and must be preceded by a comma in Czech spelling.

Why is it nové muzeum and not nový muzeum?

Because muzeum is a neuter noun (ending in -um), and adjectives must agree with the noun in gender, number, and case.

masculine: nový dům (new house)
feminine: nová škola (new school)
neuter: nové muzeum (new museum)

Here, muzeum is in the nominative singular neuter (it’s the subject), so the adjective is nové (neuter nominative singular), not nový (masculine).

What does které refer to, and what case is it in?

Které is a relative pronoun meaning which/that, and it refers back to muzeum.

muzeum is neuter singular.
The relative pronoun must agree in gender and number with what it refers to, so you use které (neuter singular).

In this sentence, které is the subject of the verb má (has) in the relative clause:

které má velkou sbírku umění → which has a large collection of art.

So které is in the nominative case (subject).

Could I use který or která instead of které?

Not in this sentence. The form of který/která/které must match the gender and number of the noun it refers to.

který – masculine singular
která – feminine singular
které – neuter singular (and some plural uses)

Since muzeum is neuter singular, the correct form is které.
který or která would be ungrammatical here.

What tense and person is má, and which verb is it from?

Má is from the verb mít (to have).

infinitive: mít
1st person singular: mám – I have
2nd person singular: máš – you have
3rd person singular: má – he/she/it has

In the sentence, muzeum (it) is the subject of the relative clause, so you need 3rd person singular: (muzeum) má = it has.

Why is it velkou sbírku and not velká sbírka?

Sbírku is in the accusative case because it is the direct object of the verb má (has).

nominative: velká sbírka – a big collection (as subject)
accusative: velkou sbírku – a big collection (as object)

In které má velkou sbírku umění:

subject: které (which = the museum)
verb: má (has)
direct object: velkou sbírku (a large collection)

So both the noun (sbírka → sbírku) and the adjective (velká → velkou) change to the accusative feminine singular.

What case is umění in, and why doesn’t its form change?

Here, umění is in the genitive singular.

The pattern is: sbírka + genitive = a collection of something.
So sbírka umění literally means a collection of art (collection of what? → of art).

The noun umění is neuter and has the same form in several cases (nominative, accusative, genitive singular are all umění), so it doesn’t visibly change.
But grammatically, after sbírka, it is genitive.

Can I say V našem městě je nové muzeum s velkou sbírkou umění instead?

Yes, that is also correct and very natural:

V našem městě je nové muzeum, které má velkou sbírku umění.
→ There is a new museum in our town which has a large collection of art.
V našem městě je nové muzeum s velkou sbírkou umění.
→ There is a new museum in our town with a large collection of art.

The meaning is almost the same. The second version uses a prepositional phrase s velkou sbírkou umění (with a large collection of art) instead of a relative clause které má velkou sbírku umění (which has a large collection of art).

Is the word order V našem městě je nové muzeum fixed, or can I change it?

Czech word order is quite flexible. You can say, for example:

V našem městě je nové muzeum.
V našem městě nové muzeum je. (less common, more emphatic)
Nové muzeum je v našem městě.

All are grammatically correct. The differences are mainly in emphasis and what is treated as known information (topic) vs new information (focus).

V našem městě je nové muzeum. – neutral, “In our town there is a new museum.”
Nové muzeum je v našem městě. – emphasizes where the new museum is (in our town, not somewhere else).

Why is it je nové muzeum and not something like tam je nové muzeum for “there is a new museum”?

Czech doesn’t need a special “dummy” there like English there is.
You can simply say:

Je nové muzeum – there is a new museum (somewhere; context needed).
V našem městě je nové muzeum. – There is a new museum in our town.

You could add tam for emphasis on “there” (that place), e.g.:

Tam je nové muzeum. – The new museum is there.

But tam is not required to express the existential “there is”.

How do you pronounce v našem městě and muzeum?

Approximate pronunciation:

v našem městě → [v NAH-shem MYES-tye]
- v – [v] like English v
- ná- – á is long “a” as in father (but longer)
- -šem – “š” like English sh
- mě- – “mě” is close to mye
- -stě – “stě” like stye but with palatal t, [stye]
muzeum → [MOO-zeh-oom]
- mu – like moo
- ze – like ze in zebra (short e)
- um – oom

Czech stress is almost always on the first syllable: V NÁ-šem MĚS-tě je NO-vé MU-ze-um.