John was sure that by five o'cloak,he__the milking
问题描述：
John was sure that by five o'cloak,he__the milking
a.finished b.would be finishing
c.would finish d.would have finished
选d 这段话是什么时态?为什么选d,milking表什么?
答
milk vt.
挤(牛)奶；挤…的奶；(动物)哺乳：
d是过去将来完成时：should have done ,would have done
John确信在5点左右,他已经完成了挤奶的工作.
5点左右 还没到5点 所以用将来时
到了5点 finish 已经完成 所以用have finished 合起来就是d