Simple Present Tense (for future):
a)The Simple Present Tense is used for official programmes and timetables.
i) The college opens on 23rd June.
ii) The film starts at 6.30 and finishes at 9.00.
iii) When does the next train leave for Chennai?
b) The Simple Present is often used for future time in clauses with if, unless, when, while, as (means while) before, after, until, by the time and as soon as. The Simple Future Tense is not used in such cases.
i) I won't go out if it rains, (not: will rain)
ii) Can I have some milk before I go to bed?