Learn Hardcore Croatian: U kuhinji nam ne treba ni šećer ni sol. - In the kitchen we need neither sugar nor salt.

Bold nam is the unstressed (clitic) dative form of bold mi (we), meaning bold to us. With bold trebati in the “need (something)” sense, the person who needs is in the dative, and the thing needed is the grammatical subject.

bold Treba mi šećer. = I need sugar.
bold Trebaju nam jaja. = We need eggs. The full, stressed form is bold nama (used for emphasis or when placed first).

Why is the verb bold treba singular even though there are two nouns (bold šećer and bold sol)?

In the bold treba + dative pattern, the verb normally agrees with the thing(s) needed:

Singular subject: bold Treba nam šećer.
Plural subject: bold Trebaju nam jaja. With two coordinated nouns, both are heard:
bold U kuhinji nam ne treba ni šećer ni sol. (very common, especially because these are mass nouns)
bold U kuhinji nam ne trebaju ni šećer ni sol. (formally the agreement is clearer) In careful writing, many prefer plural agreement when there are clearly two separate subjects, but singular is very common in everyday speech, especially with mass nouns or when the subject follows the verb.

Why are bold šećer and bold sol in the nominative case, not the accusative?

Because in this construction the thing needed is the grammatical subject, so it’s nominative (bold šećer, bold sol). The experiencer (the one who needs) is in the dative (bold nam). Colloquially you may hear personal bold trebati used transitively (e.g., bold Ne trebamo šećer ni sol), but the neutral, very safe pattern to learn is nominative subject + dative experiencer: bold (Ne) treba nam X.

Could I use genitive and say bold ni šećera ni soli instead?

Yes. With mass nouns, Croatian often uses a partitive genitive to stress “(not) any amount of” something:

bold Ne treba nam ni šećer ni sol. (generic: sugar/salt as items aren’t needed)
bold Ne treba nam ni šećera ni soli. (partitive: not even any sugar or any salt) Both are acceptable; genitive adds the “not a bit of” nuance.

How does bold ni … ni … work? How is it different from bold ili and bold i?

bold ni … ni … = neither … nor … (used with a negated verb): bold ne treba … ni A ni B.
bold ili … ili … = either … or … (affirmative options).
bold i … i … = both … and … In negated sentences, bold ni … ni … is the clean way to negate both items. Using bold ili (or) under negation can be ambiguous.

Do I have to repeat bold ni before both nouns?

Repeating bold ni is recommended and very common: bold ne treba ni šećer ni sol. Without repeating the first bold ni (bold ne treba šećer ni sol) is also heard and understood, but repeating bold ni on each item is stylistically neater and unambiguous. No comma is needed between two simple nouns.

Why is it bold u kuhinji and not bold u kuhinju?

The preposition bold u takes:

Locative for location: bold u kuhinji = in the kitchen (staying/located).
Accusative for motion into: bold u kuhinju = into the kitchen (movement).

Where does bold nam go? Could I put it elsewhere?

Clitic pronouns like bold nam obey the “second position” rule: they typically come right after the first stressed element of the clause. Here the prepositional phrase bold U kuhinji comes first, so we get bold U kuhinji nam …. You cannot start the sentence with clitic bold nam; if you want to start with “us,” use the full form bold Nama: bold Nama u kuhinji …

Can I start with bold Nama for emphasis? Does that change meaning?

Yes: bold Nama u kuhinji ne treba ni šećer ni sol. Using full bold nama (instead of clitic bold nam) puts emphasis on “to us,” as in “As for us, in the kitchen we don’t need …” The basic meaning is the same, but the focus shifts to “us.”

Is bold niti the same as bold ni?

Yes. bold niti … niti … is a slightly longer/ more formal variant of bold ni … ni …. Both are correct:

bold U kuhinji nam ne treba niti šećer niti sol.

Any tips on spelling/pronunciation: bold šećer, sol, kuhinji?

bold šećer: the letter bold ć is a “soft ch” (closer to the t-sound in “nature” when said quickly); don’t write bold šečer (with bold č).
bold sol: spelled with bold l, not “so.”
bold kuhinji: bold h is pronounced like the German “ch” in “Bach,” and bold nj (in bold -inja/-inji) is like the “ny” in “canyon.”

Why is there no “the” in bold u kuhinji?

Croatian has no articles. bold u kuhinji can mean “in a/the kitchen,” and definiteness is inferred from context. If needed, use a demonstrative: bold u toj kuhinji (in that kitchen), bold u našoj kuhinji (in our kitchen).

Can I rewrite the sentence in other natural ways?

Yes:

bold Ne treba nam ni šećer ni sol u kuhinji. (same parts, different order)
bold Možemo u kuhinji bez šećera i soli. (We can do without sugar and salt.)
bold Nije nam u kuhinji potreban ni šećer ni sol. (lit. “is not necessary to us …”)

Would this look different in Serbian/Bosnian?

Slightly. Croatian standard prefers bold sol for “salt,” while Serbian standard uses bold so (Bosnian allows both). So you might see:

bold U kuhinji nam ne treba ni šećer ni so. Everything else (bold u kuhinji, bold ne treba, bold ni … ni …, bold nam) is the same.