seismic phase

例句：

1. 1. The earthquake was so powerful that it shook the whole city.
   地震非常强烈，震动了整个城市。
2. 2. The seismologist is studying the causes of the recent earthquakes.
   地震学家正在研究最近几次地震的原因。
3. 3. The seismograph records the movement of the ground during an earthquake.
   地震仪记录地震期间地面的运动。