will 和 be going to 和 will be doing

a future fact(will) :

The sun will set at 9:16 p.m. tonight and will rise at 4:44 a.m. tommorrow.

a prediction(will/be going to):

In 100 years humans will live/are going to live on Mars.

will:

a future probability: A: Do you think Amy will like this gift I bought her? B: I'm sure she'll love it.

a spontaneous decision(will): A: We don't have any food in the house. B: OK, I'll order us a pizza.

a promise(will): I will alway be your best friend.

a present habit(will): My husband will drink tea from time to time.

be going to:

a prediction based on present evidence: The road is gonna flood with all this rain.

a plan you have(be going to): I'm going to walk to work tomorrow to get some exercise.

will be doing:

an action in progress in the future: In 1 hour I'll be getting my kids ready for bed.

something you will not be doing again: I won't be using that lipstick again. it smelled bad.

a polite question: Will you be bringing your new boyfriend to the wedding?

an interrupted future action: The food will be baking in the oven when you get home.

a present action that will continue: I'll still be editing this video later today.

an assumption about a present action: Don't go outside now. It'll be freezing.