同学你好，该知识点来自沪江网校《大学水平直达CATTI二级（笔译+口译）3年畅学班【老学员专享】》的课程，想要更系统的学习，欢迎进入课程学习。不仅可以和更多的同学一起学习，而且还有老师、助教随时的学习指导和知识点解答哦。

同学好~

在这里Were it not for = If it were not for。这是非真实条件从句。它的意思是“如果没有”、“要不是由于”。
在if条件从句中，如果含有were, should, had等动词，则可以通过主谓倒装的方法来取消连接词if，从而变成无连接词条件从句。在正式语体中，if it were not for可以写成无连词的形式：were it not for。例如：
Were it not for your help, I would still be homeless. 要是没有你的帮助，我仍然会无家可归。
They might live quite comfortably were it not for a quarrel with their next door neighbor. 他们如果没有和邻居吵架，可能会过得很舒服。
（注意were it not for一般是用于现在情况虚拟）

如果要表示过去的非真实的条件，则使用if it had not been for。例如：
If it hadn’t been for the rain, we would have had a good harvest. 要是没有下雨的话，我们就会获得大丰收了。
If it had not been for Margaret, I might not have understood. 要是没有玛格丽特，我可能还没有弄明白。 在正式语体里， if it had not been for 可以写成无连词的形式： had it not been for。例如：
Had it not been for the doctor’s care, I should not be speaking to you now. 要是当时没有医生的治疗，我现在就不能和你说话了。

希望帮到同学~