Question

_for the fact that she brokr her leg,she might have passed the exam.

A.Had it not been
B.Hadn't it been
A与B的区别

Answer 1

考察的是虚拟语气~
当虚拟条件句的谓语动词含有were,should,had时，if可以省略，这时条件从句要用倒装语序，即把were,should,had等词置于句首，这种多用于书面语。
Should he agree to go there,we would send him there.
　　要是他答应去的话，我们就派他去。
Were she here,she would agree with us.
　　如果她在这儿的话，她会同意我们的。
Had he learnt about computers,we would have hired him to work here.
　　如果他懂一些电脑知识的话，我们已经聘用他来这里工作了。
Had it not been for the bad weather we would have arrived on time.
若不是天气坏，我们就准时到达了。

所以这道题不是选B，是选A的~相信我哦~~
希望能帮到你O(∩_∩)O~

Answer 2

B 是倒装结构，此题选B ，要不是的意思

Answer 3

If虚拟中，if除去，从句需要倒装，就如if it were not 要变成were it not.在这里要特别注意not的位置，所以答案选A