Okay thank you. In my understanding "the smaller cat" and "the cat is smaller" isn't really any difference. But from a grammatical point of view I get it know. Thank you.
Many thanks ! Now, I notice you've used the copula here, instead of tá. Would that be an instance of 'emotional estimation' as Ó Siadhail puts it, as in 'Is deas í do léine'? ' 'An-scríbhneoir ba ea í.'? Or is there another rule that you always use the copula with a comparison?
I didn't use the copula - I quoted an entry from the NEID that does what I said you shouldn't do, translating an English idiom directly into Irish.
But the reason for using the copula is because "best" is really being used as a noun in "you are the best" or "it's not the best" - it's standing in for whatever noun the definite article is there for.
You're asking the wrong question - the Irish for "cat" is cat, not chat, so the question you should be asking is "Is there anything in this sentence that would cause cat to be lenited in this sentence?".
And the answer to that question is "No, there isn't anything in this sentence that would cause cat to be lenited".
The basic reasons why a word is lenited are introduced in the Tips & Notes for the lenition skill: https://www.duolingo.com/skill/ga/Lenition/tips-and-notes