By the time she left school ,she ___ that course for ten years.A.taught B.has taught C.had taught D.will have taught
问题描述：
By the time she left school ,she ___ that course for ten years.A.taught B.has taught C.had taught D.will have taught
by the time不是用将来完成时?
答
选C.
过去的过去,用过去完成时.
这句话的意思是“她离开学校的时候,已经教这门课教了10年了.”