The simple past tense (for example, worked) is used to describe an action that has been completed. The past progressive (was or were working) is used to describe an action that was in progress at some point in the past.
Examples and Observations:
- "I was working on the proof of one of my poems all the morning, and took out a comma. In the afternoon I put it back again."
- "I was reading the dictionary. I thought it was a poem about everything."
- "I had some eyeglasses. I was walking down the street when suddenly the prescription ran out."
- "1492. The teachers told the children that this was when their continent was discovered by human beings. Actually, millions of human beings were already living full and imaginative lives on the continent in 1492. That was simply the year in which sea pirates began to cheat and rob and kill them."
(Kurt Vonnegut, Jr., Breakfast of Champions, 1973)
- "I met this wonderful girl at Macy's. She was buying clothes and I was putting Slinkies on the escalator."
- "As we were talking outside, it was cold, we were shivering yet warmed by the subject matter . . ..
"I was hoping, I was hoping we could heal each other.
I was hoping, I was hoping we could be raw together."
(Alanis Morissette, "I Was Hoping." Supposed Former Infatuation Junkie, 1998)
- "A few days later, I was studying when Auntie Annie called me into the living room. Mark was standing there, frowning at the shining Christmas ornaments."
(Cynthia Kadohata, In the Heart of the Valley of Love. Univ. of California Press, 1997)
- At the very moment that the iceberg struck, the saloon passengers were singing "A Life on the Ocean Wave."
- The Past Tense and the Past Progressive
"Often the action expressed with the past progressive was ongoing at the time another action occurred. In such cases, the action that occurred is expressed with the simple past, and the sentence generally includes a subordinate clause that begins with when or while. With when, the past progressive action can be in the main clause, as in (39a), or in the subordinate clause, as in (39b).
(39) a. He was studying for his exam when I saw him this afternoon.Although most textbooks stress the use of the past progressive in sentences like those in (39), quite frequently the past progressive is used in sentences like (40), in which two ongoing actions in the past were occurring simultaneously:
(39) b. She accidentally cut her hand while/when she was chopping vegetables for a salad.
(40) She was studying in the library when I was talking to Tom."(Ron Cowan, The Teacher's Grammar of English. Cambridge Univ. Press, 2008)
- The Present Progressive and the Past Progressive
"The difference between are walking and were walking is that the present progressive refers to an event as taking place now, whereas the past progressive tense refers to the event as having taken place at a particular moment in the past.
The men walk with their heads down. (simple present tense)To form a progressive tense, a form of be is used, which must be followed by a present participle form (-ing) of a verb."
The men are walking with their heads down. (present progressive tense)
The men were walking with their heads down. (past progressive tense)
(Marjolijn Verspoor and Kim Sauter, English Sentence Analysis: An Introductory Course. John Benjamins Publishing, 2000)