positive: negative:
I am = (I'm)
he is = (he's)
she is = (she's)
it is = (it's)
we are = (we're)
you are = (you're)
they are = (they're)
I am not = (I'm not)
he is not = (he's not)
she is not = (she's not)
it is not = (it's not)
we are not = (we're not)
you are not = (you're not)
they are not = (they're not)