Given an abstract argumentation framework ({p,q},{(p,q)}) in which an argument p attacks another argument q, argumentation semantics normally concludes that p is accepted and q is rejected. To reject p, on the other hand, a counter-argument attacking p is to be introduced. However, a player participating in an argumentation or a person in the audience of a public debate would have opinions such that “I do not believe p”, “I still believe q”, or “I do not believe that p attacks q” without any concrete grounds. In this study, we introduce the notions of AF with beliefs and belief extensions to represent interaction between arguments and beliefs. Those notions are used for modelling the audience of argumentation, dialogue between two agents, and inner conflict of an agent.