Page 427 - Practical English Usage 3ed - Michael Swan, Oxford

action, or that interrupted it,
~
past (2): past progressive (I was working etc) 422
simple past with finished time expressions
One day, the Princess decided . .. 1sawJohn yesterday.
422 past (2): past progressive (I was working etc) 1 forms
was/were + -ing 1 was working.
Were you listening to me? She was not trying.
For derails of question structures, see 480-486. For negatives, see 367-371. For passive forms (e.g. Work was being done), see 412.
For double letters in words like sitting, stopping, see 562.
2 use: What were you doing at eight o'clock?
We use the past progressive to say that something was in progress (going on) around a particular past time.
What were you doing at eight o'clock yesterday evening? - I was watching TV, (NOT ylhttt ditl}'6t1 d6 ...? - I I:tt4tMetl n~)
When 1got up this morning the sun was shining, the birds were singing, ... (NOT ••• the Still shtme, the bil'm sting ...)
past progressive: things happening around a past time Whatwereyoudoingat8o'clock?- 1waswatchingTIl.
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PAST 8 on NOW
3 past progressive and simple past: 'background' events
We often use the past progressive together with a simple past tense. The past progressive refers to a longer 'background' action or situation; the simple past refers to a shorter action or event that happened in the middle of the longer
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