We can use the present progressive to talk about future actions and events that are already planned or decided.
- What are you doing this weekend?
- I am seeing Susie this evening.
Note that the present progressive is mostly used to talk about personal arrangements and fixed plans.
- What are we having for dinner?
- I am getting a new job.
- We are going to Paris this summer.
- Are you coming to the library?
Be going to
The structure be going to can be used to talk about plans. This is common in an informal style.
- She is going to get married.
- I am going to get a good job.
- We are going to buy a new car.
- Alice says she is going to call in this evening.
Differences between the two structures
In many cases, we can use both present progressive and be going to to talk about the future. However, there are some differences.
We do not usually use the present progressive to make predictions about events that are outside people’s control.
- Look at the sky. It is going to rain before long. (NOT It is raining before long.)
Both structures can be used in commands and refusals.
- I am sorry, you are not taking my car. OR I am sorry, you are not going to take my car.