go off英音：['gəu ɔf]美音：['go ɔf]
1.响起
The alarm went off.
警铃骤然响起.
2.变质
This milk has gone off.
牛奶变坏了.
3.入睡
Hasn't the baby gone off yet?
婴孩还没入睡吗?
4.进行
The plan went off well.
计划进行得很顺利.
turn on英音：['tə:n ɔn]美音：['tɝn ɑn]
打开;发动
Will you turn on the radio?
你打开收音机好吗?
turn off英音：['tə:n ɔf]美音：['tɝn ɔf]
关掉
Turn off the light before you leave.
离开前请把灯关掉.
close down英音：['kləuz daun]美音：['kloz daun]
停业
The shop has already closed down.
那家商店已经关门了.