sudden 
英 [ˈsʌdən]  美 [ˈsʌdən] 
n. 突然发生的事

adj. 突然的，意外的；快速的

例句：
She started to thank him, but a sudden movement behind him caught her attention. 

她正开口谢他时，他身后突然有动静，吸引了她的注意力。

He had been deeply affected by the sudden death of his father-in-law. 

岳父的猝死使他十分伤心。

I hope,' the stranger said, `that the sudden change of venue did not inconvenience you.' 

那位陌生人说：“我希望突然改变地点没有给您带来不便。”

It was all very sudden. 

一切都非常突然。