赖世雄教你学英语语法
虚拟语气
5-6：but for
＝ if it were not for
若非/要不是……
此类句型仅限于与现在事实及过去事实相反的虚拟语气。
1．与现在事实相反：若非……就……
(if it were not/but for+名词）+(that从句/for+名词）+主语+（could/would/might/shold/ought to）+原形v
例：if it were not that he works hard, i wouldn't like him.
= if it were not for him hard work, i...
= were it not for his hard work. i...
= but for his hard work, i...
（要不是他很努力工作，我不会喜欢他。）
2．与过去事实相反：若非当时……就……
if it had not been+(that从句（过去时）/for+名词）+主语+（would/could/might/should/ought to）+have+p.p.
例：if it had not been that he lent me the money, i could not have bought that book.
= if it had not been for the money(which) he lent me, i...
= had it not been for the money(which) he lent me, i...
= but for the money(which) he lent me, i...
（要不是当时他借钱给我，我无法买到那本书。）
注意：but for亦可用介词without代替，之后仍接名词。
例：but for his help, i couldn't do it.
= without his help, i couldn't do it.
（若非他的帮忙，我无法办这事。）
but for his timely warnign, i might have been killed.
= without his timely warning, i might have been killed.
（若非他及时警告，我可能已经被杀了。）