中文摘要：

重新探讨了强地震前地下流体趋势异常,获得了一些认识：地下流体异常不一定存在完整的趋势、短期和短临等异常类型,但趋势异常普遍存在；地下流体特别是地下水位的趋势性异常,其开始时的形态不一定为缓慢变化；地下流体趋势异常不一定具有时空转移特征；地下流体趋势异常可能为“共同前兆”.

英文摘要：

Some knowledge is gained by re-investigation on the trend anomaly of underground fluid before strong earthquake： there is not necessarily a complete trend anomaly, short-term anomaly, short-impending anomaly etc, but the trend anomaly of subsurface fluid exists in common. The trend anomaly of underground fluid especially the trend anomaly of underground water level, and its initial shape is not necessarily slow change. The trend a- nomaly of underground fluid does not necessarily have space-time migration characteristics. The tendency anomaly of underground fluid may be a ＂common precursor＂.