have been

题目

have been

答案

你的意思是have been doing吗?这是现在完成进行时的结构.现在完成进行时(have been doing)用法：表示某一动作开始于过去某一时间,延续或重复地出现至今,或将继续延续至将来.　例：We have been working on this proj...