It’s a major         for Obama and his national security team, to fulfill the goal once voiced by Obama’s predecessor, George W. Bush, to bring to justice the mastermind （设计者）of the 9-11 attacks.

One of the consequences of our planet's being warming up is a（n）_______ in the number of natural disasters. 

You should follow _____ of the medicine, and take three pills every day.

Some famous singers live on the _________ from their record sales.

The train arrived twenty minutes late, but we were not told what caused the ____. http:/