任何人都能得到地图数据(有很多的免费来源)，但是转由转向数据的建立和维护起来代价都分外的昂贵。
Anyone could get map data (there are many free sources), but turn-by-turn data was remarkably expensive to build and maintain.
任何人都能得到地图数据(有很多的免费来源)，但是转由转向数据的建立和维护起来代价都分外的昂贵。
Anyone could get map data (there are many free sources), but turn-by-turn data was remarkably expensive to build and maintain.
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