¡La mejor respuesta!
I am doing my homework
you are my friend
he is a great student
she is my girlfriend
we are a happy family
they are looking for the treasure
i´m not a crazy boy
you're not invited to the party 
he isn´t studing English
she isn´t working at home
I am a pilot my father is in New York My sister is a nurse Charles is a good studen´t Monica is in Peru My grandpa is very tall My cousin is short My mom is beautiful Ernest is fat because he eats a lot My dog is 15 years old You aren't a doctor she isn't a police officer they aren't London My aunt isn't a good woman My son isn't sick Martha isn't in her house Terry isn´t an honest person Mark isn´t in USA I'm not sad we aren't in a party are you ok? is he at school? is she an architect? is Megan a good painter? are we students? are they in North Carolina? am I a nice husband? are you at the university? is Camille a selfish person is Tony in California?