Realise this is a very old question----- Hello - Dia duit (pronouce deea gwit, although this varies slightly from the dialect you speak) Goodbye - Slán (prounouced schlawn) better and more polite to use is Slán lat which means goodbye to you. I was talking to Irish to a fellow Irish friend in Germany and his pronounciation was different (His was Connemara Irish whereas mine would be closer to Munster Irish.