No one can tell how many sufferings the kidnapped boy ________ when he was rescued yesterday.
John can finish this task quickly ______ using better methods.
It may be necessary to stop _____ in the learning process and go back to the difficult points in the lessons.
The driver stopped his car so _____ that he was hit by the cab right behind him.
None of the students in the class likes the professor, who is used to being _____ of everything they do.
Africa is a very _____ continent, with each country, or even each part of a country having its own unique culture.