21.   Things were going swell right up to the moment the boat went end over end.

22.   When an oblong object that is not equipped with stabilizing fins is thrown or shot, it usually becomes unstable and tumbles end over end.

23.   As the conference on cities neared an end Thursday, supporters and opponents were fighting to the end over reproductive and sexual rights.

24.   German authorities have held up his MiGs for days on end over the years, reluctant to allow transit for Russian warplanes.

25.   It went end over end.

26.   It will be capable of walking across the space station end over end like an inchworm.

27.   The floor leaps up and everything is in free-fall again, somersaulting end over end.

28.   They blame the inherent design of the rounds, noting that their shape and velocity made them unstable in flight and liable to tumble end over end.