Question

Preciso colocar essa frase ai para o interrogativo, como procedo?
My classmates are preparing project.

Answer 1

Are my classmates preparing project? 

Answer 2

Are my classmates preparing project?

Para se colocar na forma interrogativa, você inferte o to be
Exemplo, na afirmativa é
I am
You are
He is
She is
It is
We are
They are

Na interrogativa você inverte
Am I?
Are you?
Is he?
Is she? 
Is it?
Are we?
Are they?

fica assim, no simple presente.