The oringinal question: 鸭子落到圆形湖中,狐狸在岸边想吃鸭子。鸭子受伤,无法从水里起飞,必须游到岸边才能起飞。狐狸在岸上跑的速度是鸭子速度的4倍,问鸭子是否可以游到岸边起飞跑掉?how? I think,nobody can understand your method ,even smart brother.Anyway,thank you.