Sometimes you feel tired, it is not satisfied that your smile remains. Keep smiling Although it will not make you feel much better but would not have made it worse.
Sometimes you feel disgusted not satisfied, ask your smile still keep smiling, even though it will not make you feel better, but how much is not constant, it's worse than ever.
Sometimes you feel tired, not satisfied, then let your smile is still saying he smiled. Though it was, you don't have much the same as feel better. But it would not have made it far worse than before.