We use the past continuous tense to talk about actions that were ongoing or in progress at a specific time in the past. The document provides examples of using the past continuous to describe background situations and ongoing actions. It also explains that the past continuous is not used with stative verbs and is not the preferred tense for repeated past actions. Finally, the document contrasts the past continuous with the past simple tense, noting that the past simple is used for completed actions that may interrupt ongoing past continuous actions.