"She is opening her book."
Translation:Tá sí ag oscailt a leabhar.
The possessive adjectives don’t have distinct genitive forms. Irish doesn’t have possessive pronouns such as English “mine”. It instead uses one of two constructions:
- mo cheannsa, etc. for singular nouns and mo chuidse, etc. for plural nouns;
- copula + emphasized combined form of le, e.g. Is liomsa é for “It is mine”.
The first construction also doesn’t have distinct genitive forms; I’m not sure if the second construction could be used genitively.