1、not … until，until A. until表示动作、状态的持续，强调“一直到……为止”，或强调某个动作或状态一直持续到另一个动作或状态出现之前。

2、常与表示延续性动作的动词连用。

3、如: * I waited until three o’clock, but he didn’t come. * He lived with his parents until he graduated from college. B. not … until表示“到……为止;直到……才”，常与表示瞬间性动作的动词连用。

4、如: * The noise of the street didn’t stop until midnight. * The children didn’t come home until it was dark. * I didn’t know the truth until you told me.