I will be back in three days.为什么要有be 为什么不是I will back in thr

I will be back in three days.为什么要有be 为什么不是I will back in thr ----------will he be back 答语是He will be back in two days ,I I will be back in a minute.back不是动词吗?为什么前面还要加be呢? I will be back in five minutes. i will be right back为什么will后要有个be呢?去掉be不行吗 He will be back in four days she will be back in three days 对 in three days 进行提问 1.I will be back [ ] seven days. “I will be back! 我会回来的英语是I will be back,为什么不是I will back?back不是动词吗,为什么要加be I will be back 和I will back.为什么要加be? The will be back in(a few days')time.为什么加s’