英语语法分析

"Foreshock" and "aftershock" are relative terms.

答：“前震”和“余震”是两个相关的术语。

The earthquake sequence is foreshock-mainshock-aftershock.

地震序列类型为前震—主震—余震型；

The research on the quiescent foreshock is of great theoretical and practical significance.

寂静地震的研究具有重要的理论与实际意义。