Greek has four cases, which means that three parts of speech – pronouns, nouns, and articles – each have up to four forms, depending on how they are used in a sentence. (And that doesn’t even include gender and number differences! More about
those in future lessons.)

1. Nominative case – Ονομαστική

Also known as the "naming case," the nominative is the form of nouns and
pronouns that serves as either the subject or the complement of a verb.

Ο Μάρκος μένει στην Αθήνα.   Markos lives in Athens.
Είναι γιατρός.   He’s a doctor.

2. Accusative case – Αιτιατική

The accusative is the case used for direct objects and objects of prepositions.

Ξέρω τον Μάρκο.   I know Markos.
Μιλάω με τον γιατρό.   I’m talking to the doctor.

3. Genitive case – Γενική

The genitive case is used for many different things, including

  • Possession
  • Indirect objects
  • Characteristics, nouns describing other nouns (e.g., history book)

(I haven’t studied this yet so will add examples later.)

FWIW: My Greek teacher says that the genitive is always introduced as the second case.

4. Vocative case – Κλητική

The vocative case is used only when addressing someone.

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