The simplest example is "I don't speak Spanish - YET". By adding yet, it may mean that I may take on the challenge of learning the language and speaking it.
Jack Canfield talks about when one says "I can't" they should consider saying "I won't". Is it that you truly can't or that you decided not to do so?
(Another thing I sometime do in order not to get "framed" by someone else...when they say "You are so selfish?" I, may at times, answer "Thank you for telling me that I care about myself." It is a form of reframing. Throughout the day people try to "frame" us into their world, into their way of thinking. At times that is a good thing and at times, we know we don't want to be in their "frame" but they got us with their language. A good read on this would be Robert Dilts' Sleight Of Mouth).
Anyway, just saw this video that was moving and shows how a few words can truly change a world:
P.S. Great copywriting lesson too!
P.P.S. When you have a few moments, I would appreciate you reading my story and how I am creating it: