用be going to改下句子

用be going to改下句子1.My mother visits the museum once a year.(this afternoon) My mother ( ) ( ) ( ) ( ) this afternoon.如果用 括号里填is going to visits,那句意不就改变了吗?原句是"妈妈打算今天下午去看电影",如果按那样填,不就成了"妈妈今天下午去观看"????