four dimensional fundamental form

例句：

1. 1.The four-dimensional space is filled with infinite possibilities.
   这个四维空间充满了无限的可能性。
2. 2.The four-dimensional space has been explored by astronomers for decades.
   天文学家已经探索了四维空间几十年了。
3. 3.The four-dimensional space is a fascinating subject that attracts many people's interest.
   四维空间是一个引人入胜的主题，吸引了许多人的兴趣。