yeah, or:

The nominative or dative plural adjective is lenited after a noun that ends with a slender consonant. In other cases, it isn't lenited.

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

I agree with Lughaidh. The most succinct way is to say '...if the noun ends in a slender consonant'. This is how I learned it. So the genitive therefore doesn't break the rule: Hataí na bhfear beag.

Caoirigh beaga appears to break the rule. It is an exception (to the above rule) really, but is different due to the fact that caora is not in the first declension.

PS I'm in France now (and dictionaryless - help!) so may well end up mixing up my languages!

don't be afraid, it would be difficult to mix up French and Irish grammars

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

*Tá ocras agam - J'ai faim.

_________________
Múinteoir Gaeilge - Irish Teacher
My "specialty" is Connemara Irish, particularly Cois Fhairrge dialect, but I can also speak Ulster and Munster Irish with native-level pronunciation.
Is fearr Gaeilge ḃriste ná Béarla cliste, cinnte, aċ i ḃfad níos fearr aríst í Gaeilge ḃinn ḃeo na nGaeltaċtaí.
Gaeilge Chonnacht (GC), go háraid Gaeilge Chois Fhairrge (GCF), Gaeilic Uladh (GU), Gaelainn na Mumhan (GM), agus Gaeilge an Chaighdeáin Oifigiúil (CO).

Nominative singular (ainmneach uatha): Níl ach fál amháín ansin. = There is only one fence there.
Nominative plural (ainmneach iolra): Tá na fálta móra go léir briste. = All of the fences are broken.
Genitive singular (ginideach uatha): Tá barr an fháil seo salach. = The top of this fence is dirty.
Genitive plural (ginideach iolra): Tá barra na bhfálta sin go léir briste. = The tops of those fences are all broken.

Correct at will! Next noun: fuinneog = window

_________________

iontach deas

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

Ag bumpáil

_________________