单选题 If I ______ harder for the final exam, I should have passed it.
  • A. study
  • B. had studied
  • C. studied
  • D. was studying
【正确答案】 B
【答案解析】[解析] 句中的陈述与过去事实相反，因此从句用had studied，主句用should+have done 的形式。