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1.
certainly is one of those words that makes you sound exponentialy more intellegent that you really are. it is very much like "indeed" in it's usage and effect. Works best if you put the word "well" or "why" in front of it, and if you use "truly?" as a question.
Joe: hey did you read that chapter in history?

you: why certainly winstin.

joe:...
by the will burchfield August 15, 2006