Well in the 'Black North' we're taught to say 'cad é mar atá tú.

Lady in my class from Tiobraid Árann says the greatest single thing that differentiates individual speakers is this question...and then after that it's all a practically indistinguishable blur

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Níl mórán Gaeilge agam (fós). Is foghlaimeoir mé...agus is breá liom é!

Is fearr Gaeilge bhriste, ná Béarla cliste.

"Cad é mar atá tú" is the standardised Ulster spelling form of "Goidé mar atá tú". Just like, "Conas atá tú" is the prefered standard and the standardised form of the Munster form: Cionnus/ Cionnas 't(h)ánn tu or Cionnas 't(háir) or Cionnas taoi"

There exists,within the standard/ caighdeán oifigiúil, a small leniency for dialectal variation. There has been a recent amendment to the caighdeán allowing the Ulster treament of the Réamhfocail/ prepositions to be allowed- i.e leniting instead of eclipsing.

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Please wait for corrections/ more input from other forum members before acting on advice

nothing recent there, have a look at New Irish Grammar by the Christian Brothers...

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Is fearr Gaeilg na Gaeltaċta ná Gaeilg ar biṫ eile
Agus is í Gaeilg Ġaoṫ Doḃair is binne