Future Forms

WILL + INFINITIVE

INSTANT DECISION: I will have the steak.

PREDICTION (not based on evidence): It will rain next week.

OFFER: I will carry your bags.

PROMISE: I will not tell anybody.

FUTURE FACT: The election will be in December.

SHALL + INFINITIVE

OFFER: Shall I help you with your homework?

SUGGESTION: Shall we eat out tonight?

TO BE GOING TO + INFINITIVE

FUTURE PLANS AND INTENTIONS: Tomorrow, I am going to wash my car.

PREDICTION (based on evidence): Look at the black clouds. It is going to rain.

PRESENT CONTINUOUS

FUTURE ARRANGEMENTS: I am having a party on Saturday evening.

There is very little difference between the present continuous and going to for future plans / arrangements. Therefore, often you can use either.

PRESENT SIMPLE

EVENTS WHICH ARE PART OF A TIMETABLE: The film starts at 9.30

Future Plans 

FUTURE CONTINUOUS 

It is used to talk about actions or events which will be in progress at a certain time in the future: 

Don't call after eight - I'll be watching the match then.

It is also used to talk about a future action that will happen because it is regular or decided.  It can be used to ask about someone's plans politely.

Will you be coming out with us tomorrow night?

FUTURE PERFECT

It is used to talk about actions and events which will be completed by, or which continue until, a certain time in the future.

I think we'll have finished the job by Friday.

Future continuous & Future perfect

Be + about to, due to, on the verge of, set to or am/is/are + to are used to talk about something that is ready to happen.

They are about to drown in some of the most dramatic changes life offers.

Be + bound to, certain to, (un)likely to, sure to are used to say how certain we are that something will happen.

The cost of an average family holiday abroad is likely to increase under current government plans.