I
would have underdeveloped
you
would have underdeveloped
he / she / it
would have underdeveloped
we
would have underdeveloped
you
would have underdeveloped
they
would have underdeveloped
I
would have been underdeveloping
you
would have been underdeveloping
he / she / it
would have been underdeveloping
we
would have been underdeveloping
you
would have been underdeveloping
they
would have been underdeveloping