Being able to speak another language well is a great _____ when you're looking for a job．

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.

This had a great ____ the future of both mother and son.

It is a great ______ for us to be invited here to meet the great scientist face to face.

With international ______ and education exchanges increasing every year, the number of Chinese students studying abroad has increased rapidly.