am, aren't (only in inversion, as in Aren't I special?), ain't, 'm (as in I'm)
are, aren't, ain't, 're (as in you're)
be
been
can, can't
could, couldn't
did, didn't
do, don't
does, doesn't
had, hadn't, 'd (as in She'd gone out)
has, hasn't, 's (as in She's gone out)
have, haven't, 've (as in I've)
is, isn't, 's (as in She's back)
may, mayn't
might, mightn't
must, mustn't
ought, oughtn't
shall, shan't
should, shouldn't
was, wasn't
were, weren't
will, won't, 'll (as in she'll)
would, wouldn't, 'd (as in I'd go out)