In my day, if I were to puton a pair of trousers like they do now, lightning would strike me.
这个句子中。前边的 In my day明明是一个过去时间。为何后边用以后时的虚拟语气呢？是否应该用与过去事实相反的虚拟语气呢？
in my day = when I was young. 这个状语表示说话人的视角是过去，听话人的注意力也被引导到过去，这是句子状语修饰整个句子。然后从这个视角出发，假设一个与以后事实相反的条件，并由此推理出一个以后结果，if 从句和结果主句仍然分别用were to do 和 would do。所以句子是没问题的。
又如下面的故事中的虚拟语气：
He didn't do his homework. He decided to play truant. If he were to go to school and fail to hand in his homework, he would surely be punished by the teacher.
你读这段故事的时候，会不会质疑故事中的事情发生在过去，虚拟语气为何用表示与以后事实相反的动词形式呢。其实这是由于说话人的视点并非目前，而是在故事中的那一天。虚拟条件对于这个视点而言，仍然是以后时间。
