I've become severely confused about the articles an agus na.

What do they cause, as far as lenition/eclipsing, etc?

"An" is used only before singular nouns.
It lenites (except d, t, s) feminine nouns in the nominative singular, and masculine nouns in the genitive singular.
In Ulster, it lenites all singular nouns in the dative singular (except d, t, s). In other dialects, most of the time it eclipses, but there are exceptions.

"Na" is used:
- before feminine nouns in the genitive singular. Then it doesn't cause any change except that it prefixes h to vowels.
- before plural nouns in the nominative case and dative case. Then it doesn't cause any change except that it prefixes h to vowels.
- before all genitive plurals. In this case it eclipses the noun.

I hope I've not forgotten stuff

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

For the singular it depends on the gender and case:

Feminine singular nominative = an + lenition (but an + t before s)
Feminine singular genitive = na + (no mutation) (but na + h before vowels)

Masculine singular nominative = an + (no mutation) (but an + t- before vowels)
Masculine singular genitive = an + lenition (but an + t before s)

For the plural for both genders:

Plural nominative = na + (no mutation) (but na + h before vowels)
Plural genitive = na + (eclipsis) (but na + n- before vowels)

That's straight nouns. Once a preposition is added in front, it all changes (best to learn the rules for each preposition.)

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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).

Re "An":

In the nominative case, if the word following it is masculine, there's no mutation. (An fear: The man)

In the nominative case, if the word following it is masculine and begins with a vowel, it's prefixed with "t" (An t-asal: The Donkey)

In the nominative case, if the word following it is feminine and begins with a lenitable consonant other than "s", it is lenited. (An bhean: The woman)

In the nominative, if the word following it begins with "s" a "t" is prefixed (can't think of an example at the moment)

In the nominative case, if the word following it is feminine and begins with a vowel, there is no mutation (an otharlann: the infirmary)

If it's being used in the genitive case, the word following it will be masculine and singular, and it will be lenited if possible, unless it begins with "s" (Teach an bhuachalla: The boy's house). If the word begins with an "s," "t" is prefixed (teach an tsagairt: the priest's house). If the word begins with a vowel, there will be no mutation (Teach an asail: The donkey's house, aka, the toilet).

Regarding "na":

"Na" indicates either a plural noun (of either gender) in either the nominative or the genitive, or a feminine singular noun in the genitive.

In the nominative plural, the word will not be mutated if it begins with a consonant, regardless of gender: (na buachaillí: The boys. na fuinneoga: The windows.). If it begins with a vowel, "h" is prefixed (na hasail: the donkeys).

In the genitive feminine singular, there is no lenition: (na fuinneoige: of the window). If the word begins with a vowel, it will have "h" prefixed (na hotharlainne: of the infirmary).

In the genitive plural, if the word begins with a vowel, "n-" is prefixed, regardless of gender (na n-asal: of the donkeys. na n-otharlann: of the infirmaries)

I THINK that covers everything, but wait for more input, just in case!

Redwolf

Welcome to the club.

And reading up on the grammatical rules is the easy part. The tricky part is applying the correct rule on-the-fly when several people are talking at once.

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Táim ag foghlaim fós. Fáilte roimh gach aon cheartúchán.

Where's the emoticon for "head swirling around"! Haha! But I think it's becoming closer to clearer!!



I think it covers more than enough for now! That's GREAT! Thanks everybody so much!

And now for my expert input on this complex topic......

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Ha! I love when rhetorical questions turn out to have answers!! It's always hilarious, for some reason! And yes, Saoirse, you may just be a genious

Alas, still waiting to be discovered..... Ochón....

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Ah, to quote...