GIVE ANSWERS - English

In normal circumstances I am doing means the present continuous. E.g. I am doing the laundry (I am washing/drying my clothes at the moment). Whereas, I am going to would mean about the future. E.g. I am going to do the laundry (I have yet to do this action, but I am planning to do it now). However, I believe you might be also thinking of sentences when people say: I am doing the laundry tomorrow. (This would have a similar meaning to going to, whereby it expresses an action you have planned for the future)

I am doing means a present tense you're doing while I am going to do is a future tense according to me

Think of "I am doing" as something that you are doing in the immediate - in the moment, like you are actively doing something right now. "What's up?" "I am doing laundry".
Think of "I am going to do" as talking about doing something later on in the future. Use the 'going' as a way to remember this: "what's up" "I'm going to do some cleaning soon"

mac2210 Sorry, but your explanation of the difference between ”will” and ”going to” is poor, confusing and doesn’t properly explain the real difference. This is the sort of explanation that utterly confuses students. I get a lot of students, both in my course groups and privately, asking me ”what is the difference between ’will’ and ’going to’” after having gone through previous English courses and given the sort of explanation you have written in your post.

I sympathise with my students. Here’s why:

Firstly, note the keywords in the question ”when we speak about future”. will - for spontaneous decisions, promises and offers... You are actually using ”will” in a present tense form here. The decisions, promises and offers you describe are about making decisions, promises and offers - at the present point in time. This even usually applies to general predictions and opinions. All these usages of ”will” are for something which might or might not be fulfilled at a future point in time, even potentially an event emanating from the past - but something related to all this formulated in the present.

Your example ”I’ll have a burger thanks” is a request/wish for someone to prepare then give you a hamburger, not so polite in British English, relatively polite in American English and definitely more polite than saying ”I wanna hamburger!”. Hopefully the future result of that request/wish given at the present point of time is a prepared hamburger better than the garbage you get at MacDonalds.

As I’ve said, ”will” can be used for events related to events not related to the future. It could even be an event from the past!

Take for example: I hope that I will pass the exam I took yesterday (British English speakers usually use ”will” less often here). You are describing the result of an already completed event, a completed exam paper. The result is already set (unless of course the teacher is infamous for passing students who should be failed...), but you are expressing the hope that there is a pass mark for the exam - a past event. In terms of differentiating ”will” and ”going to” when actually describing a future event, i.e. actually describing the event as in the future once it has been formed as an opinion, plan or whatever....

”opinion” is a poor word choice which does next to nothing to differentiate ”will” and ”going to” - and confuses students. You tell us use ”will” for ”opinions”. Then you tell us to use ”going to” for ”predictions made based on what we can see or hear”. A ”prediction made based on what we can see or hear” is an opinion formed about a future event based on the evidence we can get from seeing or hearing up to the present point of time!

Another poor word choice is ”general” for describing ”prediction” regarding ”will” ”based on what we already know”. You also talk about using ”going to” for ”predictions made based on what we can see or hear.”. Most predictions for most normal people are based on what we can see or hear!!!! So how the hell is ”general” differentiating from ”what we can see or hear”?

For example, your sentence ”Look at those black clouds, it’s going to rain”. So, which applies: the ”general observation” that ”black clouds = rain” - in which case you should use ”will - or ”I see black clouds in the sky, therefore after I see rain”? You haven’t really differentiated between your stated cases of ”will” and ”going to”. No wonder students get confused with such explanations...

As I had explained in another post on this thread, ”will” when used to describe the future gives that an event is almost 100% certain but there is still some doubt. ”will” exists as one of the modal/auxilliary verbs used to express probability of the event in the future, going from least likely to most likely:

”could” ”might”/”may” ”should” ”can” ”would” ”will” (there are others, but they are much less common in modern English).

So, nothing difficult about all this... For a degree of doubt about the future event. one of the above auxilliary verbs and appropriate form, if an event is absolutely certain, but you don’t know when, then ”going to”. If you are sure of the time of the event, then a present tense form - present continuous for the continuity of the event or a simple present tense form for the event as a fact. Nothing complicated and that’s how native English speakers describe the future

That you can’t come up with clear examples that differentiate ”will” and ”going to” shows either that you don’t understand the definitions you gave or that the definitions themselves are rubbish.

For whatever reason, American English grammar texts are often highly problematic when they discuss grammar points and are unable to differentiate between usage for different forms. This is reflected in the inability of most American native English speaker teachers to teach grammar to English language learners....

So, I end up with students coming in nominally at a B2 or C1 level who can only express the future productively in speaking or writing using ”will”. Students should already be differentiating and productively using ”will” and ”going to” at an A2 level!

Edit:  for some reason, unable to submit response to the comments of mac2210 below. Here is my response:

I'd taught from Headway for quite a long time and know it well. Yes, I'm saying that Headway's explanation of that grammatical point is not very good.
 
Advanced Grammar by Hewings is pretty much hit and miss in general and misses very badly when talking about the future in English. Yes, I've got a copy of Hewings and I've actually read and thought about it. Some people seem to think Hewings is great because Cambridge Press glued the green-covered "Advanced Grammar" onto Murphy's red and blue book series. Murphy is actually pretty good!

Hint: a good starting point regarding the poorly formulated mess that Hewings gives for expression of the future is that a timetable is a type of plan....

That you posted a grammatical explanation essentially copy-pasted from a grammar book - without attribution - might lead one to think you perhaps don't actually understand the grammar you were speaking about...

I go into depth with all my reasoning in another post. I prefer to actually give my evidence and refute the actual content given in a post rather than the copout of name-dropping a textbook....

hey when you wants to talk about some thing in present time you should use i am doing that mean i do this work right now but when you wanna talk about something your not really sue about them or maybe they will happen in the future you use im going to do