Students find it difficult to differentiate between future forms. When you make it clear and teach them to visualise the situation it's easier for them. 1) A dark cloud refers to the be going to form-obvious facts. 2) A skidding car is for sure to crash another-be going to. 3) We were all in that situation,lying on a couch and wondering,who will answer the ringing phone. 4) Tell them to imagine what they will become one day, especially if they study hard. 5) Ask them to imagine that they are in a restaurant. They don't know what they will have since they don't know what is on the menu. So, they take a look at it, pick and tell the waiter using will: I know! I will have a pizza. Your mum/dad/friend etc. isn't listening and asks you to state what you have ordered.Then it becomes an intention and it's be going to. 6) After certain verbs you use will: know, believe, hope,think etc. 7) The planner refers to something already set,at certain time,day and in this case you use present continuous.You tell them that you can't barge in at the hairdresser or at your boss' office before setting an appointment. This helped my pupils understand future. I hope it will help you too. :)
