The past continuous tense is most often used for actions happening at some time in the past.
When we want to talk about an action that was happening over a period of time in the past, we use the past continuous tense. Look at these examples: At this time last week I was lying on the beach in Goa. My mother was working in the garden so she didn't hear the telephone when I called her yesterday. I was watching TV when she called. What were you doing at 8 o'clock yesterday? The past continuous is very often used with the past simple to say that something happened in the middle of something else. In each of the following examples, the single event (past simple) happens in the middle of a longer action (past continuous).