新概念英语3第二课一句话i've been coming up here night after night for weeks now.now是干什么的?

问题描述:

新概念英语3第二课一句话
i've been coming up here night after night for weeks now.
now是干什么的?

此句是现在完成进行时,表示一个动作从过去一直持续到现在还有可能持续到将来,例如 I have been waiting for you for hours now. for hours表示等人这个动作已经持续了几个小时了,now则表示到目前为止是up till now的缩写