A. We use the Past Simple we are talking about past events and situations:
A1. talking about an event that happened at a particular time in the past.
A2. talking about something that continued for some time in the past.
A3. talking about something that happened several times in the past, we use the Past Simple or ‘use to‘ or ‘would‘. But we do not normally use ‘would’ with stative verbs (be or know).
B. We use the Past Continuous when we are talking about something which happened before and after a given time in the past: and when we are talking about something happening before and after another action in the past.
C. When we are looking back from a point in the past to something earlier in the past (the past in the past) we use the Past Perfect.
D. when we are talking about the effects in the present of something that happened in the past, we use the Present Perfect and when we are talking about something that started in the past and still goes on.
E. The future in the past: when we talk about the future from a time in the past we use:
E1. ‘would’ as the past tense of will.
E2. ‘was/were going to’
E3. the Past Continuous