本题选择什么15.He works as a teacher now,but he________ on a farm for three years.
问题描述：
本题选择什么15.He works as a teacher now,but he________ on a farm for three years.
15.He works as a teacher now,but he________ on a farm for three years.
A.worked B.has worked
C.had worked D.works
但是我觉得应该选择B
答
He works as a teacher now,but he (once worked) on a farm for three years.
这里加上一个once会更顺一些
答案：
A.worked
一定是说过去
他现在是老师,但以前曾经在农场工作过三年.
不能选择完成时态.