I think I will be very happy!为何要加be?可以不用be?在语法书哪里?

I think we will be I think you will.I'm afraid we'll have to be leaving.I've enjoyed talking with you.Yeah,I think you will. I think everything will be OK! .i think you will be No.1 I think there will be fewer______people.I think there will be fewer jobs _____people I think i will be the best one 是什么意思 I think I'will be a reporter in ten If you marry i think i will certainly be I think I will be busy tomorrow as today. I think that I will be deadened什么意思 I think that I will be dream come cure! I think I must be crazy,I've lost my heart to you! I think i've got well 翻译 i don't think homes will have computer.i don't think there will be any I will think about I think I will miss Well,I think there will be more people. I think he will be a doctor.改为否定句