premise: A man talking on a cellphone is holding a blue banner. hypothesis: The man has his hands down by his side, empty.
contradiction: The first instance of the man states that he is talking on a cellphone (probably held in one hand) while also holding a blue banner (probably held in the other hand) while in the second instance his hands (are) down by his side, empty; a person can either have their hands full or empty at any given moment, they cannot happen simultaneously.