Ionnsaich← Home
abhainnriverfeminine noun
the
an abhainn
after a preposition
an abhainn
of the
na h-aibhne
plural
aibhnichean
the (plural)
na h-aibhnichean

Every form but the headword, the genitive and the plural is worked out by the spelling rules in the grammar guide, so what you see here is what the guide teaches. Awaiting a fluent speaker’s review.