topographic maps的用法和样例：
例句
- The analysts drew the results as vectors on a big topographic map for firefighters to see.
这些分析师在大张的地形图上以向量绘制出结果，方便消防人员理解。 - The ellipsoidal model is commonly used to construct topographic maps and for other large and medium scale maps that need to accurately depict the land surface.
椭球面模型则一般用来构建地形图或其他大中比例尺地图，以获得对地面形态更准确的描述。
