看下面英语句子分析语法

倒装
句首为否定或半否定的词语,如no,not,never,seldom,little,hardly,at no time,in no way,not until… 等.
Never have I seen such a performance.
Nowhere will you find the answer to this question.
Not until the child fell asleep did the mother leave the room.
当Not until引出主从复合句,主句倒装,从句不倒装.