Ο ξάδερφός μου μένει στην πρωτεύουσα και σπουδάζει ιστορία.

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Breakdown of Ο ξάδερφός μου μένει στην πρωτεύουσα και σπουδάζει ιστορία.

• μου: my
• μένω: to live
• σε: in

Questions & Answers about Ο ξάδερφός μου μένει στην πρωτεύουσα και σπουδάζει ιστορία.

Why does the sentence start with Ο? How do I know ξάδερφος is masculine?

Ο is the masculine singular definite article in the nominative case. It means “the”.

Greek has three genders:

• Masculine: ο (e.g. ο ξάδερφος – the (male) cousin)
• Feminine: η (e.g. η μητέρα – the mother)
• Neuter: το (e.g. το παιδί – the child)

You know ξάδερφος is masculine because:

1. It refers to a male person (male cousin).
2. Its typical masculine ending -ος matches the article ο: ο ξάδερφος.

So Ο ξάδερφός μου = My (male) cousin as the subject of the sentence.

Why is it Ο ξάδερφός μου and not something like μου ξάδερφος, like in English “my cousin”?

Greek normally expresses possession with article + noun + weak possessive pronoun:

• ο ξάδερφός μου = my cousin
• η αδερφή μου = my sister
• το βιβλίο μου = my book

So the typical order is:

[article] + [noun] + [μου / σου / του / της / μας / σας / τους]

The possessive pronoun μου (my) comes after the noun and is unstressed (an enclitic).
Saying μου ξάδερφος on its own is not standard; you need the article and the noun first: ο ξάδερφός μου.

Why does ξάδερφός have two accents in Ο ξάδερφός μου?