Please excuse me _______ your letter by mistake.
One advantage of eating a balanced breakfast is ______ it can keep you energetic throughout the day.
I think that's unlikely to happen, but if that ______ occur, both America's and China's interest would be severely damaged.
My wife ______the night shift when my plane ______. That’s why no one is to meet me at the airport today.
As I know, there is _____ car in this neighborhood.
Economic growth in the world remains weak throughout 2012 and it is hoped that it will _____ gradually in 2013.