Crear
Warnings
Predictions based on external evidence
To describe what happens in a book/movie
With stative verbs
Predictions based on the speaker's knowledge/opinion.
With recently, already, just.
For actions in the past that happened before other past actions.
Habits & routines
Plans
Changing situations
Certainty
Future use: Events on a schedule
Decisions made at the moment of speaking
Recent actions
Promises
Actions happening now
Experience
Intentions
With ALWAYS to express annoyance
With ever/never + superlative adj (Past reference)
With It's the first time/It's the worst...
Offers
Past actions with consequences here and now