如果想表达自己打算做某事、计划做某事或者有意做某事，可以用be going to do sth.的结构，例如：
● I'm going to check my email this evening.
今天晚上我打算查看电子邮件。
● He is going to have a piano lesson this weekend.
他这个周末有堂钢琴课。
● They are going to have a picnic this weekend.
他们这个周末会去野餐。
be going to在句中一般用在其他动词之前。根据be的句法要求，可以推断出be going to do sth.的否定形式和疑问形式，如下表所示：
肯定 | 否定 | 一般疑问 | 回答 |
I am going to visit China. | I am not going to visit China. | Am I going to visit China? | Yes,I am. No,I'm not. |
You are going to the park tomorrow. | You are not going to the park tomorrow. | Are you going to the park tomorrow? | Yes,you are. No,you aren't. |
He/ She is going to buy some clothes. | He/ She is not going to buy any clothes. | Is he/ she going to buy any clothes? | Yes,he/ she is. No,he/ she isn't. |
It is going to rain. | It is not going to rain. | Is it going to rain？ | Yes,it is. No,it isn't. |
We are going to have a picnic. | We are not going to have a picnic. | Are we going to have a picnic？ | Yes,we are. No,we aren't. |
They are going to have a party. | They are not going to have a party. | Are they going to have party? | Yes,they are. No,they aren't. |
如果要询问某人在将来某一段时间打算做什么，一般要说：
● What is he going to do this afternoon?
他今天下午要做什么？
● What are you going to do this weekend?
你这个周末要做什么？
● What are they going to do this evening?
他们今天晚上要做什么？
根据询问的具体情况，可以在句首加不同的疑问词，例如：
● When is Helen going to visit her granddaughter in China?
海伦什么时候去看望她在中国的孙女。
● Where is he going to have his birthday party?
他要在哪里办生日聚会？
如果表示计划到某地去，由于谓语动词go与going重复，一般可以只说“be going to+地点”，例如：
● We are going to Hong Kong for a holiday.
我们要去香港度假。
● They are going to China for a visit.
他们要去中国游览。