"我要去吃饭了"英语是I'm going to eat。
1..当be going to后接come、leave、go、等表示位置移动的动词时，直接用进行时表达。
例：Tom is leaving for Tokyo next week.
Tom计划在下个礼拜动身去东京。
2.There be结构与be going to的连用，构成There is/are going to be等于There will be。
例：There is going to be a singing competition this evening.
今天晚上将有一场歌咏比赛。