Past Progressive / Continuous
When to Use It
Past progressive tense is used to indicate that an action was in progress when another action occur in the past.
Past progressive (was/were + Ving) refers to the action in progress, and simple past tense refers to the "interrupting" action.
While I was eating dinner, the telephone rang.
The telephone rang while I was eating dinner.
When the telephone rang, I was eating dinner.
I was eating dinner when the telephone rang.
Past progressive can also be used to indicate only one action which occur in the past:
What was John doing yesterday?
He was working at the factory.
What were they doing yesterday afternoon?
They were playing
What were you doing last night?
I was studying English.
How to Make It
To make the past progressive, use the past form of "be," followed by the main verb in its -ing form.
The form of "be" (was or were) depends on the subject of the sentence or clause.
She /Jack / The cat
They /The boys
We / You