一个原因状语从句的选择题

题目

一个原因状语从句的选择题
Mr.White works with a chemicals import and export company,but he____for this industrial fair,since he is on leave.
a.has worked b.works c.has been working d.is working
我选的A.

答案

Mr.White works with a chemicals import and export company,but he____for this industrial fair,since he is on leave.
a.has worked b.works c.has been working d.is working
答案是D,我选的A.
各位仁兄可以帮忙解释一下吗?
答：D
译：怀特先生在一家化工制品进出口公司工作,但是,他现在正在为这工业博览会工作,因为他在休假中.
析:做此题的关键是要理解句子的意思,其实是句子间的逻辑.而最关键的是be on leave的正确理解.一般人很容易将它误以为是要“离去”了.其实sb.is on leave 相当于sb.is on holiday.