You use the genitive after chuid - for some words the genitive plural is the same as the nominative singular, for other words the genitive plural is the same as the nominative plural and for some words it's different from both the singular and plural nominative.
hataí is both the nominative plural and the genitive plural of hata.
I'm confused as to the meaning of the sentence in English. Does it mean that we split a certain number of hats between ourselves and I didn't get my fair share? (very weird context if that's what it is about) If not, I really don't understand the translation. Also, why would we just say "our" shoes in the corresponding exercise using cuid whereas here it's "my share of" hats? Why not "my share of" shoes (and confuse me even more)?
Cuid (part/share) is used:
- by nouns in the plural e.g.: mo chuid éadaigh (my clothes), mo chuid leabhar (my books)
- by nouns without a plural form or unquantifiable things: e.g.: mo chuid Gaeilge (my Irish), mo chuid airgid (my money), mo chuid bainne (my milk)
- by a share of something eg.: mo chuid den obair (my work / my share of the work)
So I can tell that "hata" is 4th declension.
And then the rulebook here http://www.nualeargais.ie/gnag/gram.htm says the genitive plural is the same as nominative plural....
and then shows how to form nominative plural... ~a becomes ~aí
but what's all this talk of strong plurals and weak plurals? links/references needed, thanks...