The core idea — a long action and a short one
Imagine you are in the middle of doing something — cooking dinner, reading a book, watching a film. Then something unexpected happens and interrupts what you were doing. The phone rings. Someone knocks on the door. It starts to rain.
This is the interrupted action pattern. There are always two actions involved:
The Past Continuous describes the action that was already in progress — the background. The Past Simple describes the short interrupting event that happened suddenly.
How to form the Past Continuous
The Past Continuous is formed with was / were + verb-ing. The choice between was and were depends on the subject.
You / we / they → were + verb-ing · We were watching. They were playing.
Spelling rules for -ing:
Most verbs: add
-ing → cook → cooking, read → readingVerb ending in -e: drop the e, add
-ing → drive → driving, make → makingShort CVC verb: double the consonant → run → running, sit → sitting
Affirmative sentences — the full pattern
Subject + Past Continuous + when + subject + Past Simple
I was cooking dinner when the phone rang.
Pattern B — when clause at the start:
When + subject + Past Simple, subject + Past Continuous
When the phone rang, I was cooking dinner.
Pattern C — while:
Subject + Past Simple + while + subject + Past Continuous
The phone rang while I was cooking dinner.
- I was cooking dinner when the phone rang.
- We were watching a film when someone knocked on the door.
- She was driving to work when she saw the accident.
- He was sleeping when a loud noise woke him up.
- They were having a meeting when the fire alarm went off.
Negative sentences
To make the Past Continuous negative, add not between was/were and the -ing verb. This usually corrects or contrasts what the person was actually doing.
Subject + were not (weren't) + verb-ing + when + ...
I wasn't cooking — I was reading a book.
We weren't watching a film — we were playing cards.
- I wasn't cooking dinner when it happened — I was sleeping.
- We weren't watching a film — we were playing a board game.
- She wasn't driving to work — she was walking.
- He wasn't sleeping — he was lying awake in the dark.
- They weren't having a meeting — they were having lunch.
Interrogative sentences (questions)
Were you sleeping when it happened? · Was she driving to work?
Wh- questions — asking about the background action:
What were you doing when the phone rang?
Where was she going when she saw the accident?
Wh- questions — asking about the interruption:
What happened while you were cooking?
What did he do when the alarm went off?
- What were you doing when the phone rang?
- Were they having a meeting when the alarm went off?
- Where was she driving when she saw the accident?
- What happened while you were watching the film?
- How long were they waiting when the train arrived?
Key connecting words
when and while are the most important. When typically introduces the Past Simple (interruption). While typically introduces the Past Continuous (background action).
Common mistakes to watch out for
✗ I cooked dinner when the phone rang.
✓ I was cooking dinner when the phone rang.
When two past actions overlap — one is in progress when the other happens — the background action must be Past Continuous. The sentence "I cooked dinner when the phone rang" sounds like you cooked dinner in response to the phone ringing — like a sequence, not an interruption. The Past Continuous was cooking makes it clear the cooking was already in progress when the phone rang.
✗ I was cooking dinner when the phone was ringing.
✓ I was cooking dinner when the phone rang.
The interrupting action is short and sudden — it happens at a specific moment. Use the Past Simple for the interruption. The Past Continuous was ringing would suggest the phone was ringing continuously in the background — which changes the meaning completely.
✗ I was knowing the answer when the teacher asked me.
✓ I knew the answer when the teacher asked me.
Stative verbs (know, believe, want, have, love, hate, own, understand) cannot be used in the continuous form — even in the interrupted action pattern. If the background "action" is actually a state, use the Past Simple for both verbs.
✗ While the phone rang, I was cooking dinner.
✓ When the phone rang, I was cooking dinner.
✓ While I was cooking dinner, the phone rang.
When introduces a short, sudden event → use Past Simple in the when clause. While introduces a longer, ongoing action → use Past Continuous in the while clause. Mixing these up produces unnatural English. A quick test: while = something happening over time; when = something that happens at a point in time.