球体

例句：

1. 1. The sphere of influence is the area around a person or thing that affects their actions.
   影响范围是一个人或事物周围影响其行动的区域。
2. 2.The sphere of knowledge covers all fields of study and research.
   知识领域涵盖了所有学习和研究的范围。
3. 3. The sphere of responsibility is defined by the limits of one's authority.
   责任范围由一个人的权限界限决定。