"It is orange."
Translation:Tha e orains.
You default to e if you don’t know which noun you’d use to describe it whatever it is (eg. when asking dé a th’ ann? what is it? you use masculine form ann). But if you know what it is, then as tj4234 wrote, you use the pronoun agreeing in gender with the noun you’d use to describe it (eg. you use i for weather as the words for weather are feminine in Gaelic) – especially if you use that noun somewhere else in the sentence.
When you describe an animal whose biological sex you know, you also might use the pronoun agreeing with the biological sex instead of grammatical gender of the noun (eg. i for a female cat even though cat is masculine, or e for a male bat even though the noun ialtag is feminine). And the same for humans, as with he and she in English, eg. i for a female teacher even though the nouns tidsear, muinear, etc. are masculine.