11.  A scientist does experi merits, and no experiment I have ever done proves that air pollution is hurting those trees.

12.  A sociological revolution was also taking place as the social status of owner occupation proved increasingly compelling.

13.  A story was even current to prove his manhood he had killed and castrated a boy belonging to the palace.

14.  A third reason is that some bank managers feel threatened by a measure which could prove embarrassing.

15.  A very short length of cable is supplied with the machine, and this proved annoying unless an extension lead was used.

16.  Accumulating days for sick leave proved to be a trap.