讀音：
英 [?unli if] 美 [?onli ?f]
解釋：
除非;只要…就;只有，只有當…
1.I'll do that, but only if we set a few rules.
我可以幹，但我們得定幾條規矩。
2.The placebo effect can be understood only if we acknowledge the unity of mind and body.
只有我們承認身心壹體，安慰劑效果才能被理解。
3.The lawyer is paid only if he wins
只有官司贏了才支付律師費。
4.You can make progress only if you are modest.
惟虛心乃能進步。
5.Political attacks work only if they find an echo with voters.
政治攻擊只有在選民中引起***鳴才會有作用。
6.The meat market can continue only if it is radically overhauled to conform with strict Europeanstandards.
肉類市場只有經過徹底的大檢查，嚴格遵守歐洲標準，才能繼續營業。
7.Syria will attend only if the negotiations deal with issues of substance.
只有在談判涉及重大問題時敘利亞才會參加。