Grammar

The Past Perfect tense

In the Past perfect tense, the auxiliary verb had is used with the past participle form of the verb to indicate that the action was completed before a past action or time.

The Present Perfect tense

The Present Perfect is often used to talk about actions that started in the past and have been completed at some point before the present moment.

The Past Continuous tense

The Past Continuous tense is used to describe an action

that was in progress at a specific time in the past.Situation Adverbs
Action happening at a specific time in the past at that time, then
Action happening over a period of time in the past all day/night/morning/afternoon, constantly, continuously
Two actions happening simultaneously in the past while
Repeated action in the past every day/night/morning/afternoon, always