为什么是We'll be back而不是We'll back?back不是可以做动词吗?干嘛要把他看做形容词?

为什么是We'll be back而不是We'll back?back不是可以做动词吗?干嘛要把他看做形容词? We'll Be Coming Back MP3连接 We'll ( ) on Sunday evening A、is back B、be back C、back D、are back WE‘LL BE COMEING BACK FOR YOU ONE DAY! No we'll be going back after 4 years U'll be back I'll be back I'll be back I'll be back I'll be back so I'll call on you at 10:00 tomorrow morning.Sorry,I will be enjoying the flight to Shanghai then为什么是will be enjoying 而不是 am enjoying 请问we'll be 为什么是If it doesn't rain tomorrow,we'll go there.而不是If it isn't.为甚莫不能用isn't? 改写为同义句:I think they'll be back soon.I think they'll-- soon. 英语:Inside the castle we'll be safe from the enemy.为什么是受敌人的保护? WE WILL BE BACK We will be back! we'll be back in no time.请分析一下这句话的成份. We'll be back _____ ______ _______ tomorrow morning at 7:00.