Mr. Green has two sons, and one of ______ is working as a bus driver now.
Is it only when you fail _________ you will be aware of your mistakes?
The young man was ________ of stealing money from the company in order to buy an iphone
Chinese GDP has been growing steadily year by year, _________ second in the world now.
You can go out, _________ you promise to be back before 11 o'clock.
Unless _________ by the police, you should keep silent over the accident.