No one ______ be more generous; he has a heart of gold.

If you _____ smoke, please go outside because this is a non-smoking office.

–Carla _______ go to that historical museum after school when she was a teenager. --No wonder she is so familiar with it. 

— There’s somebody at the door. Who ______ it be? Is it the postman ?—No, it ______ be him. It’s just seven o’clock. It’s too early.

The weather turned out to be fine yesterday. I ______ the trouble to carry my umbrella with me.