Be going to

​:) + am/is/are + going to + simple verb + context in the future

Use be going to, in order to express:

++Future plans: We are going to travel to Finland this winter.
++Visible predictions: It's too cloudy, it's going to rain soon.

​To make negative statements, use NOT in the verb to be.
--​She isn't going to come with us to the party.
---You aren't going to pass the exam, you never study.

Negative
statements

Present progressive for future arrangements

​:) + am/is/are + verb (ING) + future plan.

Use the present progressive to express future plans that you have already lined up and you are pretty sure they're gonna happen.

Example:
+ My friends are getting married next summer, I've been invited to the wedding.
* He is flying to London for Christmas, he bought his tickets yesterday.