precompact metric space

例句：

1. 1. In the study of relativity, we need to consider the precompact metric space.
   在研究相对论时，我们需要考虑到预紧致度量空间。
2. 2.The precompact metric space is a mathematical concept that plays an important role in the study of gravity.
   预紧致度量空间是一种数学概念，它在研究引力学中起着重要的作用。
3. 3.The precompact metric space is a theoretical framework for studying the behavior of matter and energy in space-time.
   预紧致度量空间是研究物质和能量在时空中行为的理论框架。