GbEng
那男孩忽然哭了起来。 The boy began crying all of a sudden.
起风了, 雨点忽然落下来。 A wind arose, and rain drops began falling all at once.
我一转身, 忽然看见了汤姆。 Suddenly I turned and caught sight of Tom.
他的心忽然起了疑惑。 A doubt sprang up in his mind.
这匹骡子忽然用后腿猛踢 The mule lashed out with its hind legs.
变迁,盛衰在人的一生中、活动中或者周围环境中会碰到的忽然或者想不到的变化或变迁 One of the sudden or unexpected changes or shifts often encountered in one's life, activities, or surroundings.