Once a computer is put into water, the system _______ and cannot repair itself.

Their coming without notice really                    our difficulties.

—What do you think of the news in today's newspaper?—We shouldn't ________ the trouble of helping others only because what we do may invite trouble.

I learned from my book that it was nothing but ten years of hard work that ______ his success in business.

Tom is a stubborn and careful man; It took many hours to_______ him of my good idea and to give up his.