a spacetime continuum的用法和样例：
- Gravity, which general relativity attributes to the curvature of the spacetime continuum, stubbornly resists being incorporated into a quantum framework.
- To have a spacetime as large as the visible universe, the theory must have about 1060 colors.
- There is a vein of melancholy in his character.
- There was a long lag in forwarding mail to us.
- A bowl of hot chicken soup is good for you.