spheroid of earth

例句：

1. 1. The spheroid was a fascinating object to study.
   这个球体是一个令人着迷的研究对象。
2. 2.The sphere of influence is limited by the radius.
   影响力半径是有限的。
3. 3. The sphere of knowledge is vast and ever-expanding.
   知识领域广阔且不断发展。