"He has eighty years."

[SatharnPHL]

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

[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.

[SeanMeaneyPL]

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