The past continuous tense, also known as the past progressive tense, refers to a continuing action or state that was happening at some point in the past. The past continuous tense is formed by combining the past tense of to be, i.e., was/were + verb + ing.
There are many situations in which this verb tense might be used in a sentence. For example, it is often used to describe conditions that existed in the past: The sun was shining every day that summer.
It can also be used to describe something that was happening continuously in the past when another action interrupted it: I was making dinner when she arrived.
It can also refer to a habitual action in the past: She was talking constantly in class in those days.
Based on https://www.grammarly.com/blog/past-continuous-tense/