突(忽)然的，出乎意料的(happening，coming，make or done quickly and unexpectedly)：a～attack/idea/departure 突然的攻擊/念頭/起程;a～burst of temper/turn in the road 突發(fā)的一陣脾氣/路上的急轉(zhuǎn)彎;the～arrival of the guests 客人們的突然到達(dá);sudden death 暴死;(平局時(shí)為決定勝負(fù)而延長時(shí)間)加賽決勝法;Her decision to get married is rather～. 她要結(jié)婚的決定太突然了。〖同〗abrupt，quick，speedy，rapid，immediate，instant，hasty;〖反〗slow，gradual，anticipated;
all of a sudden 突然地，冷不防地，出乎意料地：He was sitting quietly reading when all of a～a stone hurtling through the window. 他正在安靜地看書，突然一塊石頭自窗外飛進(jìn)室內(nèi)。
→′suddenly adv 相當(dāng)突然地;′suddenness n 突然