enlish小小选择题
问题描述：
enlish小小选择题
it is hard to imagine what I would be doing if I ____ in love at the age of seven with the library in my town
A didn't fall B hadn't fallen
give me a reason
答
B
if引导的虚拟语气,要在原有的时态（题目里是7岁,一般过去时）的基础上再往前推一个（所以是过去完成时）