The Future Simple Tense

will + Infinitive 

The Future Simple Tense denotes a future action :

1. You will write this exercises tomorrow.
2. I am tired. I will go and have a nap before dinner.

The Future Simple is used with the following adverbias of time: tomorrow, the day after tomorrow, next week/month/year/Monday, soon, in three days/ a week, in 2050. These adverbials go at the beginning or at the end of a sentence.

 Кроме этого, will и shall используют и  в других случаях:

Shall in offers:

Shall I get your coat for you?

Shall in suggestion :

Shall we ho to movies?

Shall in threats :

Just wait ! you'll regret this

Will in requests/invitations:

Will you open the window, please ?

The Future Simple Tense is not used after the conjunctions:

When, till, until, before, after, as soon as, as long as, if , unless, on condition that , provided , in case.