The computer (had just been turned on )when his cell phone rang .为什么用完成时态

问题描述:

The computer (had just been turned on )when his cell phone rang .为什么用完成时态
而不用过去式 (was just turned on)

表示过去的动作,对现在有影响打开电脑对电话铃响怎么会有影响呢?不好意思,看错了。过去完成时用于强调一个动作在另外一个动作(过去动作)之前发生,强调先后顺序手机响先于电脑打开的动作,过去的过去