Understanding Latin Grammar  How Latin Nouns Work Unlike English, Latin shows the function of a noun by changing its ending rather than by relying mainly on word order. These different endings are called cases. Because of this system, Latin sentences can be arranged more freely while still remaining clear. Latin has six cases, each with a different purpose:   Case Main Use Example Meaning Nominative Subject Marcus ambulat. — Marcus walks. Genitive Possession (“of”) liber Marci — Marcus’ book Dative Indirect object (“to/for”) Iuliae librum do. — I give the book to Julia. Accusative Direct object Marcum video. — I see Marcus. Ablative Means, place, manner, with/from/by cum Marco — with Marcus Vocative Direct address Marce! — O Marcus!