Ionnsaich← Home
cathairchair; cityfeminine noun
the
a' chathair
after a preposition
a' chathair
of the
na cathrach
plural
cathraichean
the (plural)
na cathraichean

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.