Read and learn about past continuous!
 
First, revise present continuous from 4th grade!
Past continuous is a verb tense used to describe actions that were in progress at a particular time in the past, often interrupted by another action. It often answers the question "What was happening?"
For example:
Yesterday at 10 a.m. I was walking to the store.
She was studying when I called her.
 
Use of Past Continuous:
  • Past actions in progress
We use the past continuous to talk about actions that were in progress (not finished) at a specific moment in the past.
For example:
‘What were you doing at 6?’ ‘I was doing my homework.’
When I saw them yesterday, they were playing football.

The specific moment in the past can be described by a time expression (at 9 a.m., at midday, at lunchtime, all morning, all day, etc.).
For example:
They were swimming at 7 in the morning.
At midday, they were still working.

The specific moment in the past can also be described by a simple past action.
For example:
They were swimming when I saw them.
When she arrived, they were still working.
 
  • Actions happening at the same time in the past
We use past continuous to describe actions that were happening at the same time in the past.
For example:
I was cooking dinner while my friend was setting the table.
They were playing football when I arrived at the park.
 
  • Repeated past actions
We can also use past continuous to describe actions that were happening repeatedly over a period of time in the past. 
For example:
When I was a child, I was playing outside every day.
He was always talking during the meetings last year.
 
  • Describing a scene
We often use the past continuous at the beginning of a story to describe the situation.
For example:
It was getting late, and I was walking home. Suddenly, …
 
Formation of Past Continuous
  • The structure of affirmative sentences:
Subject + was/were + verb (-ing).
For example:
I was reading.
You were sleeping.
 
  • The structure of negative sentences:
Subject + was/were + not + verb (-ing).
For example:
I wasn't reading.
You weren't sleeping.
 
  • The structure of questions:
Was/Were + subject + verb (-ing)?
For example:
Was I reading?
Were you sleeping?
 
Compare and Contrast
  • Past Simple vs Past Continuous:
We use the past simple for completed actions in the past, but we use the past continuous for actions in progress (not finished) in the past.
For example:
She ate an ice cream yesterday. (the action is finished)
She was eating an ice cream when I saw her. (the action was not finished)
 
The past simple describes a shorter action or event, but the past continuous describes a longer action or situation.
For example:
I met Michael while he was waiting for a bus.
We didn’t go out because it was raining.

The short action in past simple often interrupts the longer action in past continuous.
For example:
He was playing football when he broke his arm.
When I went to bed, it was raining.

We use only the past simple for completed actions that happened one after the other (chronological order).
For example:
finished my homework, ate dinner, and went to bed.

Compare these sentences: 
When we arrived, mom was making a cake. (The action of making a cake started before we arrived.)
When we arrived, mom made a cake. (The action of making a cake started after he arrived.)
Svarīgi!
The word when is often used to introduce the past simple action.
For example:
When we arrived, mom was making a cake.
Svarīgi!
The word while is often used to introduce the past continuous action.
For example:
While I was studying for my test, my friend called me.