be suddenly serious

基本解釋

The pollution result that once petroleum development in Songhua river appears suddenly accident will be very serious.
松花江上石油開發(fā)中一旦出現(xiàn)事故其污染所造成突發(fā)事故將是十分嚴重的。
WARNING: The Floormen should always be aware of the tremendous force that can be applied and that the tongs could fly off suddenly, causing serious injury or fatality.
警告：鉆工應該隨時注意巨大的拉力會造成大鉗突然飛出而造成嚴重的人員傷害或死亡。
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Serious thought needs to be done by those who live there, to plan for such an emergency, which could come upon them suddenly during a deluge.
居住于該地的人們需要對此進行認真嚴肅的考慮，為這種緊急情況未雨綢繆，因為在大洪水時，該狀況會突然出現(xiàn)在他們面前。