It _________ there is a disaster _________ people will think much of the safety.
Understanding the cultural habits of another nation, especially __________ containing as many different subcultures as the united states, is very difficult.
解析:one 代指一个国家,他是泛指
The boy was led _______while crossing the road.
______ has taken away my notebook?
Columbus is known for the great discovery _____________ a new land—America.
.–Have you seen the film? --Yes. I __________ it three times when I was in Tokyo.