unless 
英 [ʌnˈlɛs]  美 [ʌnˈlɛs] 
除非

conj. 除非

prep. 除…之外

例句：
I won't come unless you phone me. 

你不给我打电话，我就不来。

They can't vote unless they have French citizenship. 

如果他们没有法国公民身份，就不能投票。

He was told he would be killed unless he left the area. 

有人告诉他如果他不离开该地区就会被杀。

Unless he comes, we won't be able to start. 

他不来我们就不能开始。

I'm not happy unless I ride every day. 

只有每天骑车我才会开心。

Unless she was very much mistaken, he was showing off for her. 

除非是她弄错了，他是炫耀给她看的。