Is this correct??

It is very nice to see you in class today == Tá sé an-deas tú a fheiceáil í rang inniu

I can speak Irish today better than I did last year == Is feidir liom Gaeilge a labhairt inniu níos fearr ná labhair me Gaeilge anuraidh


Also, I know that I am happy == Tá athas orm,
but I'm not sure what "I'm very happy" would be.
I'm assuming you can't use "an-athas" because "athas" is technically a noun and can't be modified with "an-" which, in this case, is an adverb.
So, how would you say "I'm very happy"??

I'd say sa rang instead of i rang (without accent, btw)



ná mar a labhair ...
or:
ná a labhair ...
(rarely: seachas mar a labhair, thar mar a labhair ...)



Tá an-áthas orm.

You can use an- freely with nouns (an-áthas, an-chuid, an-rinceoir, an-seasamh, etc.)
An- is just a prefix. It doesn't convert words into adverbs and isn't an adverb itself.

it was already pointed out that "sa rang" works better here

but I also wanted to mention that it should be thú here instead of tú, at least to my understanding
tú is used as a subject and thú is as an object, as I understand it

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Wondered about that. "i rang" is more literally what I wanted to say, but "sa rang" just felt better, but wasn't sure.
BTW, don't know where the fada over i came from. Must have typed itself



So,the complete translation would be: Is feidir liom Gaeilge a labhairt inniu níos fearr ná mar a labhair me Gaeilge anuraidh??



OK, that certain makes life easier. I suppose this is another case where Irish and English don't directly correspond to each other.

Thanks much.

Wondered about "tú vs thú". Still not sure overall how pronouns changes when used as objects vs subjects

I'd say both are equally good:
tú a fheiceáil / thú a fheiceáil

tú a fheiceáil is very common.

do you know if it is permitted in the CO? not that it is really important, but I am wondering

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you mean is féidir liom


putting aside this version, what I would probably say (not sure if this is better or worse) is :
Tá Gaeilge níos fearr agam anois ná mar a bhí agam anuraidh

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