Question

There is going to be a dolphin show in the zoo tomorrow evening.为什么要加be？

Answer 1

be going to 是将要的意思，这句中就等同于will，
there will a dolphin show 你就会发现，句中缺少谓语动词，所以必须加上be作为谓语。

Answer 2

这是there be 句式的将来时态用法，它 的结构式 there is going to be 或者there are going to be .这个句式还可以用there will be 来代替，所以上面这句话还可以变成 There will be a dolphin show in the zoo tomorrow evening .

Answer 3

你好

There is going to be = There will be 

哪里将会有什么事情发生

There is going to be a dolphin show in the zoo tomorrow evening

明晚动物园将会有一个的海豚表演节目

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追问

be going to 是将要的意思为什么要加be？我还是不明白，谢谢。

追答

这样说吧

A dolphin show is going to be in the zoo tomorrow evening.

你知道 be going to do 是将要做某事
同意 be going to be 也是一样，都表示将来时，将会怎么样，将要怎么样

Answer 4

There is going to be a dolphin show in the zoo tomorrow evening.为什么要加be？
There be 存在有句型 中的be 可以被下面内容替换，主语为 BE 后面的内容

(1) is / are /was/ were

(2) be going to

(3) will be

(4) happen /exist / stand/ live

(5) has /have been

(6) There appear to be

(7) There seemed to be