"I speak Irish."
Translation:Tá Gaeilge agam.
'Tá Gaeilge agam,' is really the only correct way to say that you have the ability to speak Irish.It literally means, 'I have Irish,' which is really expressing that you have possession of the language.
'Labhraim Gaeilge,' would only be used if you were saying that you spoke Irish at a particular time. Mar shampla, (for example), if you were saying, 'I speak Irish at work,' - 'Labhraim Gaeilge ag obair.'
The phrase Tá Gaeilge agam means "I have the ability to speak Irish", it doesn't mean "When I open my mouth, Irish words come out".
English is ambiguous in this regard - it allows you to say "I speak Irish" even if you haven't spoken a word of Irish in decades, but you still retain the ability to speak Irish. Tá isn't going to show up on a "drop-down" of the 3 individual words "I", "speak" and "Irish", because none of those words mean tá.
People in Ireland can say things like "I have a little French, but I haven't spoken it in years" (they say this in English). In other places, English speakers say the somewhat illogical "I speak French, but I haven't spoken it in years". Because it is so common in English for people to say "I speak French" or "I speak Italian" or "I speak Irish", when they actually mean "I can speak French/Italian/Irish", the phrase Tá Gaeilge agam is typically translated as "I speak Irish".
Translating it as "I can speak Irish" instead wouldn't solve the problem, because the typical Irish for that expression in Is féidir liom Gaeilge a labhairt or Tá mé in ann Gaeilge a labhairt, or Tá mé ábalta Gaeilge a labhairt.
It's just an ambiguous statement in English, so you can't assume a one to one translation. Tá Gaeilge agam, Labhraím Gaeilge and Is féidir liom Gaeilge a labhairt are 3 distinct sentences in Ireland, with 3 distinct meanings that can't be adequately differentiated with the two available English statements "I speak Irish" and "I can speak Irish", but the problem is with English, not Irish.
"I have the ability to speak Irish" or "I know how to speak Irish" might be clearer - "I know Irish when I hear it" is something that people say in English, but you wouldn't use Tá Gaeilge agam to say that in English.
The ambiguity here is all in English - "I know (language)" and "I speak (language)" are not very precise.
Duolingo is very confused about which answer it wants for this sentence. The first time I came across it, tá gaelige agam was the correct answer (and even as I type this comment it says "tá gaelige agam" is the correct one at the top of the page). However just now I forgot about this exception and chose labhraím gaelige without thinking twice, and my answer was marked as correct, even though tá gaelige agam was an option too.