Given that certain letters in the expression "standard oath" somehow relate to numbers, what are the next two letters?

Letters and numbers would appear to suggest Roman Numerals.
If that is the case then the D's are the letters in question.
Now taking the question "what are the next two letters?" quite literally, I would need to follow with "E" and "F".

Since the problem category is "Numbers" I think I need to follow with Roman Numerals;
  500  D
  501  DI
  502  DII
  which means that the next two letters need to be I, I.

Posted by brianjn on 2012-02-27 20:07:31