if only引导的感叹虚拟句:表示“要是……就好了”
① 表示与现在或未来事情的感叹虚拟句中,谓语一般用过去时或would/could/should/might 动词原形。
② 表示对过去发生事情的感叹虚拟句中,谓语用过去完成时。
(3)在would rather等句中的用法
在would rather,would sooner,would just as soon,might as well和would prefer等后面所跟的从句中,也可以用虚拟语气表示愿望,意为“宁愿、但愿”。
① “would rather/ would sooner等 主语 谓语动词过去时”,表示现在或将来的情况。
② “would rather/ would sooner等 主语 谓语动词过去完成时”,表示过去的情况。
3.特殊的虚拟条件句
(1)暗含条件的虚拟语气
常见的引导暗含条件句的词或短语有:without,but for,but that,otherwise,given,provided,supposing,were it not for等。
例:Without your help,we could not have succeeded.