单选题 I was (so interested in) the video that I (watched) it (for) two hours before I (realized) it.
  • A. so interested
  • B. watched
  • C. for
  • D. realized


【正确答案】 B
【答案解析】改为had watched。因为realized是动词过去式，而watch(the video)发生在 realized之前，所以用过去完成时。