a) We use the future simple to make predictions about thefuture. It is a simple prediction; it is not based onevidence, so it may or may nothappen.
Such predictions are often introduced by verbs: think, believe, be sure, be afraid
I think it will rain at the weekend.
He hopes our team will win.
b) We use the future simple to speak about something we decide to do at the moment of speaking; it is an on-the-spot/spontaneous decision or willingness.
I’ll have the orange juice, not the apple.
I’ll pay for it by credit card.
The baby won’t sleep. (unwillingness)
He won’t listen to anything I say.
c) We use the future simple to express requests, hopes, offers,promises, warnings, and orders.
Will you open the window, please? (request)
I’ll never help you again! (warning)
I’ll copy it for you. (offer)
I won’t tell anyone. (promise)
He will carry your bag for you. (order)
d) It is better to use will to make a prediction based on our opinion or experience than to be going to.
Come to see us. John will enjoy seeing you again.
No, don’t ask Ann, she doesn’t like discos. She won’t want to go.
e) We can also use it when we speak about future events which are arranged or timetabled.
Will the meeting take part tomorrow or the day after tomorrow?