Learn Hardcore Croatian: U našoj ulici je mala crkva u kojoj za svaki blagdan pjevaju djeca iz susjedstva. - In our street there is a small church in which for every holiday children from the neighborhood sing.

The preposition u takes locative when it means “in / at (location)”, and accusative when it means “into (movement)”. Here there is no movement, just a location, so you get u + locative: u našoj ulici = in our street.

Why is the verb je after u našoj ulici and not right after the subject, like in English?

Croatian word order is more flexible than English. In sentences with biti (to be) that introduce the existence of something (“there is / there are”), it is very natural to start with the place and then put je:

U našoj ulici je mala crkva. – In our street there is a small church.

You could also say:

Mala crkva je u našoj ulici. – The small church is in our street. (now we are telling you where that already-known church is, not introducing it as something that exists).

So the position of je helps structure the information: introducing existence vs. giving a location of a known thing.

What exactly is u kojoj, and why is it kojoj and not another form?

U kojoj is a relative pronoun phrase: u (in) + kojoj (which). It introduces a relative clause and refers back to crkva (church).

The pronoun koji (which / who / that) changes for gender, number, and case:

crkva is feminine singular.
Inside the relative clause u kojoj … pjevaju djeca, the preposition u again means “in”, so it requires locative.
Feminine singular locative of koji is kojoj.

So we get u kojoj = in which, agreeing with mala crkva in gender and number, and in the locative case because of u.

Could I replace u kojoj with gdje, and would it mean the same?

Yes, you can say:

U našoj ulici je mala crkva gdje za svaki blagdan pjevaju djeca iz susjedstva.

This is understandable and often used in speech.
The difference:

u kojoj is more explicitly grammatical (shows gender, number, case) and feels slightly more formal or written.
gdje (where) is simpler and more colloquial; it doesn’t show agreement with crkva.

Both are acceptable, but u kojoj is the more “textbook-correct” relative clause referring specifically to crkva.

Why is it u kojoj and not u koju after u?

Because u can take locative or accusative, depending on meaning:

u + locative = in, at (static location)
u + accusative = into (movement / direction)

Here the meaning is “in which (church)”, a static location, so locative is needed: u kojoj.
U koju (accusative) would mean into which (church) – that would only fit if there were movement into the church described at that point.

Why is it za svaki blagdan literally “for every holiday” when the meaning is “on every holiday”?

In Croatian, za + accusative is commonly used with time expressions to mean on / for each (occasion), especially for holidays and special days:

Za Božić – on / for Christmas
Za Uskrs – on / for Easter
Za svaki blagdan – on every holiday

So although literally it looks like “for every holiday”, idiomatically in time expressions it corresponds to English “on every holiday”.
The noun blagdan is in the accusative singular (svaki blagdan) because za requires accusative in this meaning.

Could I say svakog blagdana instead of za svaki blagdan?

Yes, you could say:

… u kojoj svakog blagdana pjevaju djeca iz susjedstva.

Here svakog blagdana is genitive singular, and it also expresses habitual time (“on every holiday / every holiday”).

Difference in nuance:

za svaki blagdan – slightly more event-like, often used with festive activities tied to a particular day.
svakog blagdana – more like “on each holiday (as a rule)”, a bit more neutral.

In most contexts, both are acceptable and very close in meaning.

Why is the verb pjevaju before djeca? Would djeca pjevaju also be correct?

Both orders are grammatically correct:

pjevaju djeca
djeca pjevaju

Croatian word order is flexible and often used to highlight information:

pjevaju djeca – starts with the action (sing) and then specifies who does it. It can sound slightly more neutral or descriptive in this kind of sentence.
djeca pjevaju – starts with children as the topic, then mentions what they do (sing).

In this sentence, pjevaju djeca iz susjedstva just sounds natural, focusing on the activity as a regular occurrence there.

Why is djeca used with a plural verb pjevaju, even though English “children” is grammatically plural but the word shape looks singular?

In Croatian, djeca is grammatically neuter plural, even though it doesn’t end in a typical plural ending. You can see that from:

It takes plural agreement: djeca pjevaju (children sing).
An adjective would also be plural neuter: mala djeca, dobra djeca.

So the verb pjevaju is 3rd person plural, correctly agreeing with djeca.
In English, “children” is also plural, so in that sense the agreement is parallel; the difference is just that djeca doesn’t show the plural with an obvious ending like -i, -e.

Why is it iz susjedstva and not iz susjedstvo?

The preposition iz (“from, out of”) always takes the genitive case.

Susjedstvo (neuter, “neighborhood”)
Genitive singular: susjedstva

So iz susjedstva literally means “from (the) neighborhood”.
Using iz susjedstvo would be wrong because it leaves susjedstvo in nominative (dictionary form) instead of genitive.

What’s the difference between iz susjedstva and iz našeg susjedstva?

Both are correct; iz našeg susjedstva just adds the possessive “our”:

iz susjedstva – from the neighborhood (context usually makes it clear which one).
iz našeg susjedstva – from our neighborhood (makes it explicit).

Našeg here is genitive singular neuter (agreeing with susjedstva), because iz requires genitive: iz + našeg + susjedstva.

Why does našoj end in -oj in u našoj ulici?

Našoj is the feminine singular locative (and dative) form of naš (our). It has to agree with ulici in:

gender: feminine
number: singular
case: locative (after u in the sense “in”)

So the pattern is:

Nominative: naša ulica – our street
Locative: u našoj ulici – in our street

The -oj ending is typical of feminine singular dative/locative adjectives and pronouns.

Could I add jedna and say U našoj ulici je jedna mala crkva? Does that change the meaning?

Yes, you can say:

U našoj ulici je jedna mala crkva…

Jedna is the numeral “one”, often used like an indefinite article (“a / one small church”). Nuance:

Without jedna: U našoj ulici je mala crkva… – There is a small church in our street. (neutral; Croatian normally doesn’t mark definiteness).
With jedna: can slightly emphasize “one particular small church” or “there is (at least) one small church”, sometimes introducing it as something new or a bit special.

It’s optional; many speakers would omit jedna in a neutral description.

What aspect and tense is pjevaju, and why that choice here?

Pjevaju is present tense, imperfective aspect, 3rd person plural of pjevati (to sing).

Imperfective aspect is used for:

ongoing actions
habitual or repeated actions

Here, za svaki blagdan pjevaju djeca iz susjedstva describes what regularly happens on every holiday, so the imperfective present is exactly what you want. If you talked about a single completed event in the past, you’d normally switch to a perfective verb or a perfect tense form.