If you want to say something like this

An raibh siad ag teacht trí fhuinneog nó trí dhoras?

Would you have to repeat the preposition all the time?

And if you were to drop the repeated preposition would the second noun be lenited?

...trí fhuineog nó d(h)oras?

And would an adjective following the noun be lenited in this case?

...tri fhuinneog bhriste... or ...trí fhuinneog briste?

I think so.



normally you don't need to ask yourself this question since you repeat the preposition

And would an adjective following the noun be lenited in this case?



bhriste because fuinneog is feminine.
Now, is it lenited after a masculine noun?... good question.When there's no article, I think it depends on the dialect and even maybe on the age of the speaker.
Normally when the masculine noun is in the dative case after the article, a following adjective is lenited (ar an éan bheag, leis an fhear mhór...), but when there's no article, it depends, as I said (le fear mór / le fear mhór).

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

No, I don't think you have to repeat the preposition each time, but it depends on the sentence really. Although, its more common to do so. Usually, the second noun is lenited if the réamhfhocal is not repeated.



That's a good question and there's no easy answer. It depends on dialect. Usually (In the standard, I think), the adjective is only lenited if the noun is feminine. However, in Ulster lenition is so strong after prepositions that the following adjectives are always lenited.

i.e

ar an chrann bheag etc...

In Munster, I think the more modern way is to lenite also,

a(i)r an gcrann bheag

However, the more traditional way in Munster is to follow on with the same kind of inflection that occurred to the noun i.e

a(i)r an gcrann mbeag

Crossed with Lughaidh

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

According to the original Teach Yourself Irish, i.e., the Ultimate Authority for Munster Irish (well, for Cork Irish anyway):

The initial consonant of an adjective is aspirated after a noun in the dative singular, both masculine and feminine:

fé bhróig mhóir "under a big shoe"

ar láir bháin "on a white mare"

ó dhuine chríonna "from an old person"

i gcúinne bheag "in a small corner"

do bhuachaill bhocht "to a poor boy"

In Old Irish, certain prepositions were followed by the accusative case, and a noun in the accusative normally eclipses ; other prepositions were followed by the dative case, and a noun in the dative case normally lenites.
In Modern Irish, all that got mixed up, that's why certain dialects say "ar an mbord", others "ar an bhord" (or tábla) and the adjectives are lenited or not, or even eclipsed in Cork

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

I agree with Lughaidh on this one - I was taught that you definitely repeat the pronoun.

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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).

Yep! You can get away with it, but we're not yet at the stage as we are in English where it's basically accepted to do so in speech.

Thank you all for your help...it seems like the perpetual Irish grammar answer "Yes, but there are exceptions."

The Christian Brothers need to update......"The Exceptions of Irish Grammar in three Volumes with a short Appendix defining the Rules."

Most exceptions are already mentioned in the grammars of the Christian Brothers
There's another problem: their grammars (at least the modern ones) are in standard Irish, and standard Irish has to choose its rules from one dialect or the other (or from older Irish that nobody speaks anymore...)... there are exceptions within one dialect, and when the other dialects have different rules and different exceptions... no wonder it's hard to explain everything in a grammar book (even in quite a big one )

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

Yes, I'm with you there. I don't particularly have a dialect and that's why I am asking so many questions about grammar.
I see different ways of constructing phrases and they are sometimes, to me, incongruous. Thanks for your patience, well thank you all for your patience in explaining things to me.