AFFIRMATIVE
She is happy.
Correct!
Luisa is my best friend.
She is my best friend.
at home / your mother / is/ ?
Is your mother at home?
They is my friends.
INCORRECT!
They ARE my friends.
are / open today / the shops/
the shops are open.
My brother ________ in the house.
is
Are she an actress?
INCORRECT!
IS she an actress?
are / my hands / cold
My hands are cold.
We are students!
CORRECT!
Your friend/ happy / is / very
Your friend is very happy.