The city had been carefully planned and was laid out in a series of concentric rings.这座城市经过了精心规划，布置成了一系列同心环的格局。The centres of concentric circles coincide.同心圆的圆心重合。The street plan of the city has evolved as a series of concentric rings.该城市的街道平面图像一圈圈的同心圆环。