Past continuous tense – English editing.

This tense is formed by was or were followed by the Present Participle of the main verb:
He was writing.
Uses:
To show how one event occurred during another event:
While they were talking, they heard a terrific roar.
To refer to a completed event that went on over a period of time:
I was working there in 1933.
This tense is sometimes referred to as the ‘imperfect’ tense.
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