11.  The plan, for obvious reasons, was being kept secret.

12.  There was no obvious reason for their behavior.

13.  This arrangement must be kept secret, for obvious reasons.

14.  Top of the list - and there are obvious reasons for this - comes the printing trade.

15.  Unfortunately it is not easy - for obvious reasons - to study modern submarine lava flows in their proper environment.

16.  For obvious reasons the police cannot give any more details about the case.

17.  There was no obvious reason why this could not be as good a film as the original.

18.  For obvious reasons, I would not like to reveal my name.

19.  They did not, for the obvious reason that the cash crop companies have no interest in developing food crops.