Uncle Tom has worked as a teacher __ he left school in 1999.a.before b.since c.after d.for大哥大姐帮帮忙,选什么,为什么这样选,

分类: 作业答案 • 2022-08-10 10:08:48

问题描述：

Uncle Tom has worked as a teacher __ he left school in 1999.a.before b.since c.after d.for
大哥大姐帮帮忙,选什么,为什么这样选,

答

B
典型的现在完成时 since 后加过去时前面用完成时
有不明白的地方再问哟，祝你学习进步，更上一层楼！ (*^__^*)

答

b since引导的时间状语从句,主句用现在完成时态.