Futuros (this explanation is not complete and it only shows a general and basic difference):
Will – decisiones espontáneas que se toman mientras se habla:
look! I have one euro in my
pocket! I will buy some bread!
Going to – decisions
espontáneas ya tomadas:
before I have seen that I don´t have bread, I´m going
to buy bread tomorrow
before I
have found a euro in my pocket, I´m going to buy son e bread with it
Presente simple – planificadas y no dependen de nosotros:
the train leaves tomorrow at 7.30
Presente continuo
– planificadas y dependen de nosotros:
we are leaving tomorrow at 7.30 by car
Links
explaining future forms:
This is the
best explanation in Spanish, very clear, with a lot of exercises at the end:
Another explanation
in Spanish:
Explanation
in Spanish with video:
Spanish
explanation with exercise:
Explanation
in English with exercises:
Explanation
in English with a comparison with French:
Explanation
of future forms in English: