1. If it were not for ... / If it hadn’t been for ... (要不是因为……)，
这是表示与现在事实相反的非真实条件句，其后面的主句也需使用虚拟。
If it were not for this shortcoming, he would be a fairly good coach.
要不是有这一缺点，他可能会是一个相当好的教练。
If it weren't for you, I wouldn't be alive today.
如果不是你，我今天不会还活着。
If it were not for my job, I’d come with you.
如果不是有我的这份工作，我会跟你一道去的。
If it weren’t for his wife’s money he’d never be a director.
如果不是他妻子有钱，他永远不会成为一个董事。
If it weren't for Dad, I wouldn't be where I am today ．
如果没有爸爸,就不会有今天的我。
If it weren't for Rachel Carson, the environmental movement might not exist today ．
如果不是瑞秋·卡森，现在可能就没有环境运动了。
The earth would be a frozen ball if it were not for the radiant heat of the sun
如果没有太阳辐射的热量，地球就会变成一个冰球。
If it were not for the vapour in the air, there would be no dew.
如果空气中没有水气，就没有露水。
If it were not for the liberation, my whole family would have been ruined.
如果不是解放，我早已家破人亡了。
If it were not for his help, I wouldn’t go home now.
如果没有他的帮助，我现在都还没有到家。
If it hadn’t been for the determined captain, all the passengers on the board wouldn’t have been.
如果不是这位意志坚定的船长，船上的所有乘客都不会活着。
Dismissing small talk as unimportant is easy, but we can't forget that deep relationships wouldn't even exist if it weren't for casual conversation ．
我们很容易忽视寒暄的意义，但需要记住如果没有这些随意的对话，深厚的感情也就不复存在了。
高考真题- 2018 全国2卷 阅读D
2.这个句型也有省略倒装形式：If it were not for=Were it not for
In the 1790s Tom Paine taught plebeian radicals that mankind would live in harmony were it not for the vested interest which princes, diplomats and soldiers had in promoting wars to enrich themselves.
汤姆·潘恩在18世纪90年代教育平民激进分子时论述到，如果不是为了实现王公、外交官和士兵借发起战争而使自己富有的潜在利益，人类本会生活在和谐之中。
Arrows would continue to fly forward forever in a straight line were it not for gravity, which brings them down to earth.
要不是重力使箭落向地面，它们将永远以直线往前飞行。
Were it not for this misfortune, he might never have been forced into the business of grinding out novels to support his family.
要不是因为这一不幸变故，他可能永远都不会迫于无奈地开始流水线式创作小说养家糊口。
Were it not for the fact that I saw it with my own eyes, I wouldn't believe it.
若非我那时亲眼看到，我是不会相信的。
Arrows would continue to fly forward forever in a straight line were it not for gravity, which brings them down to earth.
要不是重力使箭落向地面，它们将永远以直线往前飞行。
Were it not for your help, I wouldn't be doing so well.
若不是你帮忙，我现在不会干得这样好。
Were it not for you, all may have been lost.
要不是你，所有人都会死。
Were it not for your help, I would still be homeless.
要不是你帮助，我会仍然无家可归。
3.如果要表示过去的非真实条件句，则使用If it had not been for:
If it had not been for the doctor's care I should not be speaking to you now.
要不是医生的照料我现在就不能跟你讲话了。
If it had not been for:=Had it not been for
She might have forgotten her completely had it not been for recurrent nightmares.
要不是因为反复做噩梦，她可能已经把她彻底忘了。
Had it not been for his family, He'd have gone away long ago.
要是没有家眷拖累，他早就远走高飞了。
Nicholas might not have survived this snowstorm had it not been for TV.
如果不是看电视,尼古拉斯可能不会在这场暴风雪中幸存下来。
高考真题- 2015 北京 阅读A