I would never have amounted to anything were it not for adversity. I was forced to come up the hard way. — J.C. Penney, Entrepreneur
词汇：amount to 达到；adversity 困境；come up 走上前来，引申为进步。
句法：第一句使用了虚拟语气，表示与过去事实相反的假设。表示与过去事实相反的假设时，一般结构为：If + had done, would have done。当 if 引导的非真实条件句含有 were, had(完成时助动词), should 时，可以省略 if，并把 were, had, should 置于句首。因此，I would never have amounted to anything were it not for adversity. = I would never have amounted to anything if it were not for adversity.
If it __________ for his invitation the other day,I should not be here now. （2016江苏）
A. had not been B. should not be
C. were not to be D. should not have been
答案：A。句子意思：如果他前几天没有邀请我的话，我现在就不会在这里出现了。根据 the other day（前几天）可知，if 引导的非真实条件句假设的情况与过去事实不符，所以其结构为 if + had done。符合这一点的是A选项。另外，这是一个错综时间虚拟条件句，if条件句假设与过去事实不符的情况，主句则为这种假设下现在应有的结果，所以使用了 should do 结构（should 也可以替换为 would）。