I thought animals couldn't speak on Etheria?

Well...that's the impression I got in the 1st episode of She-Ra when the Inkeeper was shocked to hear Cringer speak. (and of course there was Kowl but I was guessing he was like an Owl...so to speak).

We never heard Spirit speak until he first transforms into Swift Wind and I figured that was pretty simple...the magic and all gave him the power to speak as well as fly.

But in several episodes of Season 1 - Pt 1 - Spirit is talking to Adora in his normal form.

Of course I also don't understand the bit of trivia in one ep that says Spirit was a girl for almost 50 episodes....I always thought Spirit/Swift Wind was male....the voice alone pretty much was a dead give away.