Solución ejercicio 5 to be negativo

Ejercicio 5. Escribe en negativo las siguientes frases. Usa la forma contracta.

a) I am happy.  
I'm not happy.
b) You are my friend.
You aren't my friend.
c) He is my brother.
He isn't my brother.
d) She is my sister.
She isn't my sister.
e) It is my dog.
It isn't my dog.
f) We are at the zoo.
We aren't at the zoo.
g) You are at home.
You aren't at home.
h) They are at school.
They aren't at school.