cease doing/to do
　　
cease to do　 長時間，甚至永遠停做某事。
cease doing　 短時停止做某事，以后還會接著做。

That department has ceased to exist forever.
那個部門已不復存在。

The girls ceased chatting for a moment when their teacher passed by.
姑娘們在老師走過時，停了會聊天。