4只乌龟做游戏。另有7只乌龟也要参加，一共有几只乌龟？9y2['X7S,Z.`.r
算式：提示9|6z.z+?+r2e9y2['X7S,Z.`.r
答：一共有1x-C-a1{5K3C.b只乌龟。9y2['X7S,Z.`.r