The young man came riding full speed down the road on his bicycle._________ it was!
— What's wrong with your uncle? — We're sure _______ something is wrong with him, but we doubt _______ the disease can kill him.
Did your father tell you _______?
Nowadays, more and more people would rather ____ __ in the country, because there is ______pollution there than in the city.
Dr. Ma is strict ______ local doctors and nurses, especially________their skills.
---When did you go to bed last night? ---______________