I am not a native English speaker, i don't understand deeply English language. So i just want to ask you this.
Many years ago, maybe before 2000, i seldom heard English people say “Uh huh”, “Uh huh” when expressing that they are understanding in a conversation. Instead, most people use "ok","ok" to express that they understand what the opposite person is talking.
But now i heard this word every where, they even use this term in country like China & many other countries (I means some Chinese people use "Uh huh" in their conversation is not rare though English is not their language).
I think “Uh huh” in other countries (especially in Asia) is a quite rude expression if u say like that to older people.
So, When was “Uh huh” invented? is “Uh huh” a formal English?