Their coming without notice really our difficulties.
As a result of __ is now known in physics and chemistry, scientists have been able to make important discoveries in biology and medicine.
These teenagers don’t know much of the world yet; that’s why they are so easily _____.
It is the interaction between people, rather than the events __ occur in their lives, __ is the main focus of social psychology.
Harry, would you _____ the story at the point where John left off yesterday?
It is reported that there is going to be a heavy rain, so I am forced to __ my visit.