Mr.Smith, there's a man at the front door who says he has news for you ________ vital importance.
The population of China is larger than ______ of any other country in the world.
Modern science has given clear evidence ______ smoking can lead to many diseases.
This is the first time that we ________a film in the cinema together as a family .
He was told that it would be at least three more months ___________he could receover and return to work.
— Can the project be finished as planned?— Sure. it completed in time, we’ll work two more hours a day.