Hi,

I'm a 16 year old boy from Finland, and i'm currently in high school.
Recently, i had an English test in which we had to translate Finnish sentences into English, and some had question tags in it. For those who don't know what they are, here's an example:
Richard lives in Australia, doesn't he?

Ok to the point now,

There was 1 sentence which we had to translate, and according to the teacher i didn't translate it right. Translated from Finnish it would be this:

I am your new teacher, am I not?

Ok so according to my teacher that is wrong, and it should be:

I am your new teacher, aren't I?

So I got 119 out of 120 points just because of that, now to be very honest, I am *** off, because I'm 99% sure that my answer is correct, and that's why I ask you guys.
Which one is correct?
Am I not,
or
Aren't I?

Both are correct, but we say the aren't version 99.999% of the time.

Am I not sounds old-fashioned and hyperbolic. You might hear it in an old play, for example, or in a very fancy speech where the speaker wants to add a rhetorical flourish.

Good luck if you try to argue with your teacher. That's usually pretty hard to do.

Best wishes, Clive

CB