Fill in the ______ first and then wait for the interview in the next room.

The scientists were trying to look for all possible _______ as to where this species came from.

I am sure David will be able to find the library-he has a pretty good___ of direction.

In the time of social reform, people’s state of mind tends to keep       with the rapid change of society.

No one has yet discovered who is responsible for the incident but the police are already collecting ______．