Here's a great resource that will tell you more than you ever wanted to know about this: http://www.nualeargais.ie/gnag/praepos.htm You can click on each preposition to see what you have to do to nouns that follow it. Based on that, centonola's sentence is foirfe (bonus points for use of Gaeilge???) everywhere except for Ulster, where they lenite the heck out of stuff. The rest of Ireland says ar an mbus and ar an bóthar, but in the north they say ar an bhus and ar an bhóthat. So if you screw up, you can just blame it on your granny from some other area of Ireland.
I'm also just a learner, so that sentence was my best guess at a sad cat. Elsewhere, I've always seen "ar an" eclipse the noun that follows, hence "ar an gcat." "Cat" is masculine, so it never gets lenited with "an" (unless it's genitive). Even if the noun were feminine, the eclipsis would take precedence over the lenition caused by the article.
It's cool. I'm still a little hazy on lenition vs eclipsis, and in what cases. I did reread the notes from eclipsis and you're correct that after "ar an" you would add g to cat, and it is indeed masculine, which is why it's "an cat" instead of "an chat." It's goofy in my head because I'm used to other languages treating cat as feminine (Die Katze).
This morning I was fiddling around in an online dictionary and saw that brónach is another word for sad, so I think you could say "Is sé an cat brónach" as another way to say "The cat is sad." But don't hold me to that.
Thanks very much!
Don't forget that German also has "der Kater" for a masculine cat! And Spanish, too, has both "el gato" and "la gata." I looked for a specific Irish word for a feminine cat, but I only found "caitín", and that is (ironically) masculine! Perhaps someone else knows if there's a word for pussycat.
And I completely agree: the whole lenition/eclipsis thing is one of the hardest things about Irish to get used to. But there's some comfort in the fact that it doesn't have the boatload of word endings that some other languages have!
True. I know that English has all kinds of language warts, but I do like that it's got no genders for nouns. I mean, if the rules were more regular like Spanish or Portuguese (or I grew up with the system) then I'd be okay with it too, obviously.
But I totally agree that it's nice to not have to learn a bunch of word endings.
I'm sure once we encounter the words enough, it'll just become second nature. I mean, I already think of beef as being mairteoil/mhairteoil without putting too much thought into it. After your response I looked at wikitionary and saw that it's got a lot of Irish words in it, and it shows their mutations, gender, etc. http://en.wiktionary.org/wiki/mairteoil