Did Tolkien Focus Mostly on the Elvish Language?

Quenya and Sindar are related languages already. I don't know what the origin of the dwarves are. All I know is the dwarves have like a secret language. Not much of it is figured figures in the books. Zoroastrians use two varieties of semi-comprehensive Persian. Latin with the Catholic Church, there's Sanskrit in a lot of Buddhist areas. Polly is more common for the Buddhist food.