To be
He and she doesn't know the answer.
He and she don't know the answer.
I come from China. I is Chinese.
WRONG I come from China. I am Chinese.
We lives in Brazil.
WRONG We live in Brazil.
She, You and I speaks Chinese.
She, You and I speak Chinese.
Clarice doesn't works every day.
Clarice doesn't work every day.
People from Germany is called Germans.
WRONG People from Germany are called Germans.