Study this example situation:

Yesterday Karen and jim played tennis. They started at 10 o'clock and finished at 11.30.
So, at 10.30 they
were playing tennis.
They were playing = they were in the middle of playing.
They had not finished playing.
Was/were -ing is the past continuous:
I/he/she/it we/you/they | was were | playing doing working etc. |
I was doing something = I was in the middle of doing something at a certain time. The action or situation had already started before this time, but had not finished:

- This time last year I was living in Brazil.
- What were you doing at 10 o'clock last night?
- I waved to Helen, but she wasn't looking.
Compare the past continuous (I was doing) and past simple (I did):
Past continuous (in the middle of an action)
- I was walking home when I met Dan.
(in the middle of walking home) - Kate was watching TV when we arrived.
| Past simple (complete action)
- I walked home after the party last night.
(= all the way, completely) - Kate watched television a lot when she was ill last year.
|
We often use the past simple and the past continuous together to say that something happened in the middle of something else:
- Matt phoned while we were having dinner.
- It was raining when I got up.
- I saw you in the park yesterday. You were sitting on the grass and reading a book.
- I hurt my back while I was working in the garden.
But we use the past simple to say that one thing happened after another:
- I was walking along the road when I saw Dan. So I stopped, and we had a chat.
Compare:
- When Karen arrived, we were having dinner. (= we had already started before she arrived)
| - When Karen arrived, we had dinner. (= Karen arrived, and then we had dinner)
|
Some verbs (for example,
know and
want) are not normally used in the continuous (see Unit 4A):
- We were good friends. We knew each other well. (not We were knowing)
- I was enjoying the party, but Chris wanted to go home. (not was wanting)