Future with "Be Going To"

To form it, we use the correct form of "Be" + "Going to"+ base form

Use: Beside "will" and "shall", we can also use "be going to" to express future events as per below situations.

1. When you intend to do something in the future:
1. I am going to buy some books this weekend.
2. He is going to cut that tree down.
3. She is not going to study geography this semester.
2. When you have planned to do something in the future (previously made decision):
1. I am going to move out soon.
2. They are going to visit their grandparents this New Year Day.
3. What are you going to do this weekend? 
3. When you can forecast (based on current situation) that something is likely to happen very soon: 
1. Look! The tree is going to fall down.
2. Watch out! He is going to fall into the hole.
3. I think it is going to rain today. Look at those black clouds.