请教will,be going to,be to的区别?

请教will,be going to,be to的区别? 请教一个语法知识点：There ____a meeting tomorrow afternoon.A.will be B.will have C.are going to be D.is going to haveThere is going to _____a meeting tomorrow.A.be B.have C.will be D.has 请教各位：He ____ nine years old next month. A. will be B. is going to be we__swim this afternoon.A.be going to B.are going to C.will going to There _____a music festival in our school tomorrow.A、will be going to B、is going to be C、is going to D、will be going to be There( ) a meeting tomorrow afternoona.will be going to b.will going to be c.is going to be d.will go to be there__a football match tonightA.is going to have B.will haveC.is going to be D.will be going There_____a meeting tomorrow afternoon.Awill be going to Bwill going to be C;is DA:will be going to B:will going to be C:is going to be D:will go to be be going to will have There＿＿a sports meeting tomorrow afternoon.A.will be going to B.will going to be C.is going tobe D.will go to be There ? a test tomorrow.A.is going to have B.are going to be C.will have D.will be today is Monday.Tomorrow --------SundayA is going to B will C will be D is going to be ( )_____there______much rain tonight?A Will,have B Will,be C Is,going to have D are,going to be There ( )a meeting tomorrow afternoonA will have B will going to beC will be Dis going to have ( )you( )free tomorrow?NO.I ( )free the day after tomorrow.A、Are；going to；will B、Are；going to be；will C、Are；going to；will be D、Are；going to be；will be 选正确的 并翻译 Their son _____five next Thusday.A. is going to B. is going to be C.will be D.shall be He fiy to Beijing tomorrow.A.is will B.be going to C.will D.is going to. 请说明理由,越快越好____you____free tomorrow?No.I____free the day affter tomorrow.A.Are;going to;will.B.Are;going to be;willC.Are;going to be;will be D.Are;going to;will be