Danas je nedjelja.

to be

Breakdown of Danas je nedjelja.

• danas: today
• nedjelja: Sunday

Questions & Answers about Danas je nedjelja.

What are the parts of speech here, and which word is the subject?

• danas = adverb “today” (not the subject)
• je = 3rd person singular present of biti “to be” (an unstressed clitic verb)
• nedjelja = noun “Sunday” (feminine, nominative singular) — this is the subject

Why is it je and not some other form of “to be”?

Because the subject (nedjelja) is 3rd person singular. Present tense of biti:

• ja sam
• ti si
• on/ona/ono je
• mi smo
• vi ste
• oni/one/ona su

Where does je go in the sentence?

Je is a clitic and normally sits in “second position” in the clause, after the first stressed word or phrase:

• Danas je nedjelja.
• Nedjelja je danas. With longer starts, it still follows the first phrase: Sutra ujutro je ispit.

Can I leave out je?

In standard, neutral sentences you keep it. You might see it omitted in headlines or notes (e.g., Danas nedjelja.), but in regular speech and writing you should say Danas je nedjelja.