This is similar to the four uses of the Present Progressive.
The way that you construct the Past Progressive is very easy.
was/were + verb+ing
Was and Were change according to the person you are speaking about. This follows the same rule that we use in the Past Simple:
Mr. Smith was
If I want to write sentences in the Past Progressive it is very easy.
I was reading a book on my phone.
He was walking for four hours.
She was eating a pizza.
It was working!
Mr. Smith was jogging around the neighborhood.
You were speaking on the cellphone.
We were riding the train.
They were working hard.
Now we get to the interesting part.
The Past Progressive can be used in four different situations.
The First usage is an action that took a long time in the past.
We were studying English for 3 years.
She was living in Paris.
The computer was finally working properly!
The second usage is that one action that took place in the past for a long period of time was interrupted by another action.
I was washing my hair when the phone rang.
He was eating breakfast when the dog barked.
We were at the market when the fire started.
The third usage is at a specific time, an event happened that took a long period of time. In the Past Progressive, if there is a specific time mentioned, it means that it was an interruption.
At 8:00 pm. you were driving to your English class.
Last night, when he was picking his mother up from the airport, there was a traffic jam.
Last week, while I was studying for my Biology test, the power went out.
The fourth usage: Two actions in the past happened at the same time.
I was working on the computer while my daughter was washing the dishes. (Really? Not!)
Dr. Cohen was operating, while the nurses were prepping the next patient.
They were dancing while the performer was singing.
The Fifth usage: General Climate
As I walked into the store, I saw sales staff waiting on customers, the clerks were refilling the shelves, the boss was signing a form and the loudspeaker was playing soothing music.
The sixth usage of the Past Progressive is used when you want to express actions that always cause problems.
You use the adverb "always" or constantly. These words go in between was/were and verb+ing
He was always losing his car keys.
She was constantly breaking her phone.
Good luck on learning how to use the Past Progressive!
Rachael Alice Orbach