This tense is often used with the following time expressions:
... at 5.20, three o'clock, etc.
Subject + was / were + verb + ing + object(s) + time Expression
We were meeting with Jane at two o'clock yesterday afternoon.
Subject + was / were + not (wasn't, weren't) + verb + ing + object(s) + time Expression
They weren't playing tennis at five o'clock on Saturday.
(Question Word) + was / were + subject + verb + ing + object(s) + time Expression
What were you doing at two-thirty yesterday afternoon?
If you are a teacher, use this guide on how to teach the past continuous tense for more help.