Everyone and their dog has exaggerated stuff on their CV, but there seems to be a difference, to me, between the kind of exaggeration that usually goes on (I have conversational French, I am an accomplished gourmet cook, I attend high brow theatre and concerts in my spare time, I was a pivotal member of the brownie cake sale committee), and lying about a qualification, or how long you've spent in an educational establishment.
Four months turning into two years, that's not really a minor exaggeration, is it?