It is in the nominative singular.
In this sentence, radna pauza is the subject of the verb počinje, so nominative is the expected case.
You can think of the structure as:
Croatian does not have articles like the or a/an.
So radna pauza can mean:
Which one is meant depends on context. In this sentence, English would usually translate it as the break or the work break, but Croatian does not need a separate word for that.
Počinje is 3rd person singular present tense.
It matches the singular subject radna pauza.
So the pattern is:
Here, radna pauza is grammatically like ona because pauza is feminine singular, so počinje is the correct verb form.
This is about aspect, which is very important in Croatian.
Croatian often has verb pairs:
Počinje comes from počinjati and is very natural for something that is starting now or for an announcement like this.
Počne comes from početi. Perfective present forms in Croatian often do not work exactly like simple present in English. They can sound more like a future or one-time completed event, depending on context.
So for a neutral announcement such as The break starts now, počinje sada is the expected choice.
Yes. Sada means now, and sad is a very common shorter form.
So these are both natural:
The version with sada can sound a little more neutral or slightly more formal, while sad is very common in everyday speech.
No, Croatian word order is fairly flexible.
Radna pauza počinje sada is a normal, neutral sentence, but you could also hear:
Changing the word order usually changes focus or emphasis, not the basic meaning.
Yes, absolutely.
If it is already clear which break you mean, pauza alone is enough:
Adding radna makes it more specific: work break, break period at work, or simply a more formal announcement.
A rough pronunciation guide is:
po-chi-nye
A few key sounds:
So počinje is not pronounced as separate n + j sounds in English style. The nj is blended.
Because Croatian usually does not need a separate subject pronoun when the subject is already stated.
Here, the subject is explicitly given as radna pauza, so adding a pronoun would be unnecessary.
Croatian often omits subject pronouns even when there is no noun, because the verb ending already gives information about the subject. In this sentence, though, the noun phrase radna pauza already does that job.