"He has eighty years."

Translation: Tá ochtó bliain aige.

[TuathaDeDanann]

Wouldn't this be ochtó bliana since bliain has a special plural form used for counting? Or am I forgetting part of the rules?

[scilling]

Ochtó bliain is correct. A summary of the rules for nouns such as bliain can be found here.

[TuathaDeDanann]

Go raibh maith agat.

[SatharnPHL]

"Fiche bliain ag fás" - I should have remembered this one.

[SeanMeaneyPL]

Does this mean, "He is eighty"? Or am I missing something?

[TArdy44]

This is literally what they say in Irish (also in Spanish and lots of other European languages), but in English??