It is used to express regular events (schedules) and facts.
It is used to express past finished actions.
Verbs can be regular (-ed) or irregular (2nd column)
It is used to express actions in progress at the moment of speaking.
It can have a future meaning to express immediate actions in the future (sure ones).
It is used to express an action in progress during a past time.
It is used to describe an action that may have happened at some point and has consequences in the present time.
It is used to describe the past action before the simple past one.
It's the past of the past
It is used to express a future action based on beliefs or ideas.
It is always followed by an infinitive.
It is used to express a future action based on intentions and evidence.
The verb 'to be' is conjugated according to the tense of the sentence and 'to' is always followed by an infinitive.
It is used to expressed a future action that will have already been finished by then.
'By' is a marker of this tense.
It is used to express a future action in progress.