pre-earthquake的用法和样例：
例句
- The flood usually happens shortly before or after the earthquake, or accords with the foreshock and aftershock.
洪涝的发生时间有可能与震链的后震或前震比较接近，或与震链推移之进程基本吻合，反映了链程中的场态效应。 - Even in areas where foreshocks are fairly common, there is no way of distinguishing a foreshock from an independent earthquake.
即使是在前震相当普遍的地区，也无法将前震与独立地震区分开来。
