Another demonstrator was charged with obstructing the police in the course of their duty.另一个示威者被指控阻碍警察执行公务。They sold the demonstrator at half price.他们以半价卖掉了那件示范产品。Marshals tried to wrestle the demonstrator out of the room.执法人员试图将这名示威者从屋子里拖出去。A demonstrator was showing customers how the food processor worked.一个人在向顾客演示如何使用食品加工器。