he looked as thoughhe___ill for a longtime.

问题描述:

he looked as thoughhe___ill for a longtime.
were
has been
为什么用were不用has been

这里的were 不是时态中的过去式,是一种虚拟语气,表示推测.(详见英语语法中虚拟语气部分)不能和has been 比较.