What language (other than English) do you speak?

[Tetsuwan Convoy]

But it's from English... by the conventions of English phonology it should be "pock-uh-mon" (/ˈpɒkəˈmɒn/).

The cartoon consistently calls the pok ee mon, so kids being kids, is what they end up being called. Nevermind what the conventions of phonology are. The cartoon says poke ee mon. So the kids, they say da poke ee mons.

Fault lies in the voice director I guess