When to use GOING TO

The structure BE GOING TO is normally used to indicate the future but with some type of connection to the present. We use it in the following situations:

2. When there are definite signs that something is going to happen. (Evidence)

Something is likely to happen based on the evidence or experience you have.

There are some black clouds, it is going to rain - I just felt a drop.

I don't feel well. I think I'm going to throw up. (throw up = vomit)

3. When something is about to happen:

Get back! The bomb is going to explode.

1. When we have already decided or we INTEND to do something in the future. (Prior Plan)

The decision has been made before the moment of speaking.

I'm going to accept the job offer.

They're going to retire to the beach - in fact they have already bought a little beach house.