Another Word English Doesn’t Have

Last two words in the first panel of this Flo and Friends:

We don’t have a contraction for “am not.”

The word would be something like “amn’t.” I clearly remember my sixth grade teacher, Mrs. Clemens telling us that the correct form is “am I not,” and I do hear that sometimes. (I use it myself). Of course, there’s “ain’t,” but that word ain’t got no couth! I don’t know why, but using “ain’t” is something like picking your nose in public, or having your shirt on inside out.

So I guess we’re stuck with “am I not,” are we not?