He resolutely refused to speak English unless forced to.
除非被逼迫，他堅(jiān)決拒絕說英語(yǔ)。
Why did you need a room unless you were up to something?
除非你要搗什么鬼，不然為什么需要一個(gè)房間呢？
Recovery can't be sustained unless more jobs are created.
除非有更多的工作機(jī)會(huì)被創(chuàng)造出來，否則復(fù)蘇無法保持下去。