It's a hard one, because it needs practice! will = deferred decision Ex: If it rains, I won't go. In this case, the decision to go or not has been deferred. The dude is waiting to see what the weather looks like. Note: Spontaneous decisions like the one answering the doorbell, "I'll get it!", count as deferred decisions. That is a bit hard to grasp, so don't try to explain that one. Just use the following rule: Use "will" with deferred decisions or spontaneous ones. going to = decisions already made I'm off to the shops. I'm going to get some bread. I think this one is self explanatory! Use "going to" with decisions made prior to the present moment. This rule applies to ALL uses of "will" and "going to". Go on. Test it!

What I learnt is this: You use "will" to talk about predictions like "It will rain tomorrow" (it's not certain, it's something that could happen or not) You use "going to" for planned actions, such as "I'm goin to visit my aunt tomorrow" (the action was planned beforehand). It has the same use as the present continuous: "I'm visiting my aunt tomorrow/ I'm going to visit my aunt tomorrow". They have more o less the same meaning. Hope this helps! :)

"Going to" usually implies a little more immediacy. To me, it implies that you are going to do something in the near future. "I will do something", to me, implies that this is simply something you will do at some point in the future. When you say, "I will do something", I have no idea when you will do it. I only know that you will do it in the future. Often, "I'm going to do something" means you are going to do something right now...but that is not always true!