1. The most common use of the past continuous tense is to talk about something that was happening around a particular time in the past.
? What were you doing at 8 o’clock last night? I was watching television.
I started watching television before 8 o’clock and I continued watching it after 8 o’clock.
? In 1994 he was working in a small town in Poland.
? At 6 o’clock on Saturday morning we were travelling to the airport.
2. We often use the past continuous and the past simple tense together. When this happens, the past continuous describes a longer, ‘background’ action or situation and the past simple describes the action or events.
? When I woke up this morning it was raining and my father was singing in the kitchen.
? I was walking home, whistling happily, when I saw two masked men run out of the bank.
Often, the ‘action’ described by the past simple tense interrupts the ‘situation’ described by the past continuous tense.
? I broke my leg when I was skiing.
? I was playing a computer game when the doorbell rang.
Notice that the past continuous describes ‘situations’ that go on for some time – ‘skiing’ and ‘playing’ but the past simple describes ‘actions’ that happen quickly – ‘broke’ and ‘rang’.
Notice too the important difference between these two sentences.
? When they arrived, Jeff was cooking dinner. Jeff started cooking before they arrived.
? When they arrived, Jeff cooked dinner. Jeff started cooking dinner after they arrived.