Choose the correct vocative form — the case for calling and addressing people directly.
Masculine consonant names add -e: Milan → Milane, Petar → Petre, sin → sine. -telj nouns take -u: prijatelj → prijatelju. -nik takes -če: vojnik → vojniče.
Feminine -a becomes -o: Ana → Ano, sestra → sestro; -ica becomes -ice: Milica → Milice. Male -a names keep the nominative: Nikola, Luka. Neuter keeps the nominative: dete → dete. Plural vocative usually equals the nominative plural: deca → deco is an exception.