be going to结构综合运用 — 英语填空题

Amy 正在写周末计划。请从括号中选择正确的词填空，将句子补充完整。\nTomorrow is Saturday. I ___ (am going to / is going to) visit my grandpa. My brother ___ (are going to / is going to) play football. My parents ___ (is going to / are going to) go shopping. We ___ (am going to / are going to) have a happy weekend!