We need to stop it, or there could be major casualties.

我们要拦住它 否则可能造成重大伤亡。

These people want to inflict major casualties on this city.

他们想在市内造成大规模伤亡。

At present, the storm did not cause major casualties or damage, but risks remain, especially in mountainous areas where rising water and wet hillsides could trigger mudslides.

目前，这场风暴暂未造成重大人员伤亡或财产损失，但风险依然存在，特别是在山区，因为水位上涨和潮湿的山坡可能引发泥石流。