一、bainot...until指的是“直到...才”的意思，如 I did not go home until my mother called me.
1.当Not until位于句首时,句子要倒装。其结构为:Not until+从句/表时间的词+助动词+(主句)主语+谓语+...。如:
①Not until the teacher came in did the students stop talking.直到老师进来学生们才停止讲话。
②Not until next week will the sports meet be held.直到下周才开运动会。
2. not until的强调结构为:It is / was not until+从句/表时间的词+that+...。
③It was not until the teacher came in that the students stopped talking.
④It is not until next week that the sports meet will be held.
It was not until I got married that I could afford to buy a house of my own.
Go alone the street until you see the traffic light.