The thing about Hoshi Sato was that, to me, she seemed nothing more than an American of Asian descent. There was nothing about her, other than her exotic sounding name and her physical features, that was Japanese in any way."
BINA writes: DUKHAT, Hoshi was EXCEPTIONAL. She spoke I think 24 languages. How many languages do YOU speak?

It was mentioned in one episode. It was 24 or 26. She mentioned in that one episode that she wanted to rely less on the Universal Translator as well.
And as much as I like Lt. Uhura (the Communications officer in TOS), I think Hoshi was better then her in the linguistics field. In Star Trek: The Undiscovered Country, Uhura was not able to speak Klingon. And Uhura was serving on the flagship of the Federation-Enterprise. It took time for Hoshi to really get her "space legs." But she did eventually.