"must be" or "can't be"?

Gap-Fill Exercise


He's taking photos of the Eiffel tower, he a tourist.
He doesn't want to get out of bed, he tired.
He's running, he late.
She's a terrible tennis player, she a professional.
All the doors and windows are open, it cold.
He's pale and he has a fever, he ill.
They don't want to eat my sanwiches so they hungry.
What !! You come from Mars ??!! You serious !
He has a birthday cake with ten candles so he ten years old.
They have lost all their matches, they very good players