"Oidhche mhath, a Thormoid."
Translation:Good night, Norman.
OK, welcome to the vocative case. When you are talking to someone instead of about someone in Gaelic, you use what is known as the vocative case. Up until now it's been not used very much (I think balach and tìdseir had it) but basically it goes like this. If a person's name begins with a letter that can be lenited (not vowel, not sg, sm, sp, st, not d, n, l) then in the vocative the name is lenited. If after any lenition the name does not have a vowel sound at the start then 'a' is put before the name. If the person has a masculine name, then the name is also slenderised (the last vowel (if it's not the last letter) either has an i put after it or is changed to an i). Thus - Tormod -> a Thormoid. Seumas ->a Sheumais, Sìne -> a Shìne, but Anndra, Eilidh, Ealasaid stay the same because they start with vowels anyway, so don't lenite and don't have the a in front.