Learn Hardcore Croatian: Roditelji žele zabraniti cigarete u dvorištu. - The parents want to ban cigarettes in the yard.

After verbs of wanting/liking/being able (like željeti, voljeti, moći), Croatian often uses the infinitive to express the action you want to do.
So žele zabraniti literally is they want to forbid/ban.

žele zabraniti – they want to ban (intention)
zabranjuju – they are banning / (regularly) ban (actual ongoing or habitual action)
su zabranili – they banned / have banned (completed past action)

Here, the focus is on intention (they want to do it), so the infinitive zabraniti fits.

What is the difference between žele and hoće in this sentence? Could I say Roditelji hoće zabraniti…?

You can say Roditelji hoće zabraniti cigarete u dvorištu, and it will be understood.
However:

željeti (žele) is slightly softer and more neutral: they wish / want to.
htjeti (hoće) can sound a bit stronger, more like they insist / they’re determined to, and in some contexts slightly more colloquial.

In many everyday situations, they overlap, but žele zabraniti sounds a bit more neutral/polite in standard Croatian.

Why is it cigarete and not cigareta or cigareti?

Cigarete here is the accusative plural form of cigareta (a cigarette), which is a feminine noun.

Nominative singular: cigareta
Accusative singular: cigaretu
Nominative plural: cigarete
Accusative plural: cigarete

Direct objects take the accusative case, so after zabraniti (to ban/forbid), you use cigarete.
Cigareti is not a correct form for this noun.

What case is dvorištu and why does it end with -u?

Dvorištu is locative singular of dvorište (yard, courtyard), which is a neuter noun.

Nominative singular: dvorište
Locative singular: (u) dvorištu

The preposition u (= in) with a static location (no movement) uses the locative case.
So u dvorištu literally means in the yard, with dvorištu in locative singular.

Why is it u dvorištu and not na dvorištu? When do I use u versus na?

With places like room, yard, house, city, Croatian usually uses u + locative to mean in / inside:

u dvorištu – in the yard
u kući – in the house
u gradu – in the city

Na is often used for surfaces and certain set expressions (e.g. na stolu – on the table, na selu – in the countryside, na poslu – at work).
Na dvorištu is possible but sounds more like “out on the yard” (as an open area), and is less standard; u dvorištu is the default neutral choice.

Why are there no words like “the” or “a” for roditelji, cigarete, and dvorištu?

Croatian has no articles (no direct equivalent of a/an or the).
Definiteness/indefiniteness is usually clear from:

context,
word order,
sometimes from using ovaj, taj, onaj (this, that).

So Roditelji žele zabraniti cigarete u dvorištu can mean The parents want to ban cigarettes in the yard, and context tells you which specific parents/yard you’re talking about.

Can I change the word order, for example: Roditelji žele u dvorištu zabraniti cigarete?

Yes, Croatian word order is more flexible than English, but changes tend to shift emphasis:

Roditelji žele zabraniti cigarete u dvorištu.
Neutral: they want to ban cigarettes in the yard.
Roditelji žele u dvorištu zabraniti cigarete.
Slight emphasis that the banning is in the yard (maybe not elsewhere).
Cigarete žele zabraniti roditelji u dvorištu.
Much more marked; emphasizes cigarete (cigarettes) or clarifies that it’s the parents who want this.

The original order is the most neutral and natural.

Could I also say Roditelji žele da zabrane cigarete u dvorištu? Is that correct?

Yes, Roditelji žele da zabrane cigarete u dvorištu is grammatically possible and will be understood.
However, in standard Croatian, with verbs like željeti, htjeti, voljeti, the infinitive (žele zabraniti) is usually preferred, especially in writing.

The da + present construction (da zabrane) is more characteristic of Serbian and of some colloquial speech. In a Croatian textbook or formal text, žele zabraniti is the recommended form.

Why is it zabraniti and not zabranjivati? What’s the difference?

Zabraniti is perfective: it refers to a single, completed action (to impose a ban).
Zabranjivati is imperfective: it refers to a repeated/ongoing action (to be banning, to keep banning).

Here, parents want to introduce a ban (a specific, complete decision), so the perfective zabraniti is natural.
If you say Roditelji zabranjuju cigarete u dvorištu, that describes the ongoing, current practice: the parents (regularly) ban/prohibit cigarettes there.

What is the difference in meaning between Roditelji žele zabraniti cigarete u dvorištu and Roditelji zabranjuju cigarete u dvorištu?

Roditelji žele zabraniti cigarete u dvorištu.
The parents want to ban cigarettes in the yard (intention, plan; the ban may not exist yet).
Roditelji zabranjuju cigarete u dvorištu.
The parents ban / are banning / prohibit cigarettes in the yard (this is their actual rule or ongoing action now).

So the first talks about a wish/intention, the second about a current rule or action.

How do you pronounce žele and dvorištu? What sounds do ž and š make?

Approximate pronunciation:

žele – [ZHEH-leh]
- ž like s in measure or vision
- both e as in bed
dvorištu – [DVO-ree-shtoo]
- dv together, like dv in dvornik (if you know that name), or just d
  - v
- o as in or but shorter
- i as in machine
- š like sh in shoe
- u as in food

So: ž = zh sound, š = sh sound.