future tense: 
1: The present simple future is used for events that are scheduled or arranged.
       -> The train leaves at 11.00.
2: We use will or shall to make offers, promises or predictions in the future that are decided at the time of speaking. Shall is mostly used in questions and mostly with I and we.    ->  We will help you move your stuff tomorrow.
                         -> Shall I visit grandma with you?
3: We use the present continuous future for future plans and arrangements that have already been made.  -> My father is going on a business trip Wednesday.
                                    -> I am celebrating my birthday this Saturday.