解释电路的三种状态。
["1\u901a\u8def\uff0c\u7535\u6e90\u901a\u5411\u8d1f\u8f7d\u7684\u4e24\u6839\u5bfc\u7ebf\u65e0\u65ad\u5f00\u65f6\u7684\u7535\u8def\u30022\u65ad\u8def\uff0c\u5f53\u7535\u6e90\u901a\u5411\u8d1f\u8f7d\u7684\u4e24\u6839\u5bfc\u7ebf\u65ad\u5f00\u65f6\u7684\u7535\u8def\u30023\u77ed\u8def\uff0c\u5f53\u7535\u6e90\u901a\u5411\u8d1f\u8f7d\u7684\u4e24\u6839\u5bfc\u7ebf\u4e0d\u7ecf\u8fc7\u8d1f\u8f7d\u800c\u4e92\u76f8\u63a5\u901a\u65f6\u7684\u7535\u8def\u3002"]