Dw i'n dda iawn!
da
Prynhawn da,.often pronounced P'nawn da, is "good afternoon" in Welsh.
ffrindiau mawr
Cael amser da.
Mwynhewch eich gwyliau.
"You are Welsh" = Rwyt ti'n Gymreig
The only person who would understand what you said would be a Welsh person, so what good would it do you to know how to say it?
Nos da, tywysoges.
Bore da, cariad.
Ffarwél gyfaill da.
Ast noson dda
"Nos da, Tad"