Tom have been working in the library every night

问题描述:

Tom have been working in the library every night
Tom have been working in the library every night over the last three months.
在过去的三个月里,应该用过去完成进行时才对啊?

过去完成时是指过去的过去所做的事,而句中并没有具体表示过去的过去的时间词,因此不需用过去完成时.