爱华网一、从含义上讲，可与时间、地点连用
The boy didn't go to bed until his fathercame back.（指时间）
Go along this street until the bridge,youwill see the hostipal.（指地点）
二、从词性上讲，可做介词也可作连词
Most of the shops are not open until nineo'clock.（作介词）
He didn't wake up until the class wasover.（作连词）
三、从句型上讲，可用于肯定句也可用于否定句
1.用于肯定句表示主句动作或状态结束
The woman worked in the factory until1991.（表示在1991年work这个动作结束了）
2.用于否定句，形成not...until的句型，表示主句动作才开始
He didn't go to bed until the TV play wasover.（当电视剧结束时，上床睡觉这个动作才刚开始）
四、until与after，before，as soon as，when之间的转换规律
1.与after引导的时间状语转换，构成主句的否定时，until直接替换after
The scientist had supper after he finished hework at midnight.
=The scientist didn't have supper until hefinis hed the work at midnight.
2.与before引导的时间状语转换
Most of the shops are not open before nineo'clock.
=Most of shops are not open until nineo'clock.
I had breakfast before I went to schoolyesterday morning.
=I didn't go to school until I had breakfastyesterday morning.
3.与as soonas/when引导的时间状语替换时，主句变成否定句，until直接替换成as soon as，when
I'll tell him news as soon as he comesback.
=I won't tell him news until he comesback.
4.与if引导的条件状语从句的互换。若not...until转换为条件状语从句时，主句构成肯定（去掉not），用if直接替换until；若条件状语从句转换为not...until句型时，则反之，主句构成否定（加not），until直接替换if
Father won't let you watch TV until youfinish your homework.
=Father will let you watch TV if you finishyour homework.
I will give you a call if I arrive inParis.
=I won't give you a call until I arrive inParis.
