Past continuous tense: was and were plus -ing, and when to use it instead of the past simple

The past continuous is the tense that sets the scene. Where the past simple hands you a finished event, the past continuous drops you into the middle of something: I was walking home, the rain was falling, they were still arguing when I left. Nothing is complete. That is the whole point of it, and once you see the tense as background rather than event, choosing between it and the past simple stops being guesswork.

How to form the past continuous

Two pieces: the past of be, then the -ing form of the main verb.

was / were + verb-ing

The only thing that changes by person is was or were, exactly as in the past simple of be.

• Negative: put not after the auxiliary. I was not listening. They weren't waiting.
• Question: put the auxiliary first. Were you sleeping? What was she doing?

Note that be carries the past on its own, so the main verb never changes: it is always the plain -ing form. There is no such thing as "was worked" here.

Spelling of the -ing form

Study keeps its y (studying), because the doubling rule is about consonants, not vowels. And note the last row: British English writes travelling and cancelling where American English writes traveling and canceling.

What the past continuous is actually for

Four jobs, and almost every past continuous you meet is doing one of them.

1. An action in progress at a past moment

You name a time, and the tense tells you the action was already under way and had not finished.

• At eight o'clock I was still working.
• This time last year we were living in another town.

2. A long action cut across by a short one

This is the classic pairing, and it is why the two past tenses are taught together. The longer action goes in the past continuous; the shorter one that interrupts it goes in the past simple.

• I was cooking dinner when the phone rang.
• She was crossing the road when the car stopped.

The order of the two halves does not matter, only which tense each half gets: When the phone rang, I was cooking dinner means exactly the same thing.

3. Two long actions at the same time

Both are in progress, so both are continuous, usually joined by while.

• I was reading while she was cooking.
• The children were playing while their mother was working.

4. Background in a story

Open a story and the first sentences are often continuous, because they are scenery rather than plot. Then the past simple arrives and things start happening.

• The sun was going down and the air was growing cold. Then a dog ran out of the trees.

There is also a fifth, smaller use worth knowing: with always or forever, the past continuous carries a note of complaint. He was always losing his keys says more about your patience than about the keys.

While, when and as

These three words decide the shape of most past continuous sentences, and learners tend to use them interchangeably. They are not.

The rule of thumb: while and as want a continuous verb after them, when wants a simple one. It is not an absolute law, but if you follow it you will be right nearly every time. While she arrived sounds wrong for exactly this reason: arriving takes a second, so there is nothing to be in the middle of.

Past continuous vs past simple

Put them side by side and the difference is length, not time.

The pairs above are not the same sentence in two styles. I read the letter means I got to the end of it. I was reading the letter leaves open whether I ever finished, and usually implies something else came along. If you want the full picture of the finished side, see the past simple.

One more thing the continuous cannot do: put events in order. A story told in the past continuous never moves forward, because nothing ever completes. I got up, made coffee and read the news is a sequence. I was getting up, was making coffee and was reading the news is a mess.

Verbs that refuse the continuous

Some verbs describe a state rather than an activity, and a state is not something you can be in the middle of. These stay in the past simple even when the sentence is otherwise crying out for a continuous.

• Thinking and knowing: know, believe, understand, remember, forget, mean
• Liking and wanting: like, love, hate, want, need, prefer
• Having and being: be, have (= own), belong, own, cost
• The senses: see, hear, smell, taste (when they are not deliberate acts)

I was knowing the answer and she was wanting to leave are both wrong. Use I knew the answer and she wanted to leave.

The catch is that several of these verbs have a second, active meaning, and in that meaning the continuous is fine. I was thinking about you (an activity in your head) is correct, while I was thinking it was Tuesday (an opinion) is not. She was having lunch is fine because have there means eat, not own. He was seeing a doctor is fine because it means visiting, not looking.

Common mistakes

Ranked by how often they actually turn up.

1. Continuous for a finished, single event. I was breaking my leg last year. Wrong: breaking a leg takes a moment and it is over, so use the past simple. I broke my leg last year.
2. State verbs in the continuous. I was wanting, she was knowing, they were liking. Use the past simple: wanted, knew, liked.
3. Dropping was or were. I working when she called. The auxiliary is not optional; it is where the tense lives. I was working.
4. The wrong half in the continuous. I was cooking when she was arriving. Only the long action gets the continuous: I was cooking when she arrived.
5. Using the continuous to list a sequence. Events in order need the past simple. Keep the continuous for the scenery around them.

Practice

Choose the past simple or the past continuous. Answers are below.

1. We ___ (walk) home when it ___ (start) to rain.
2. At ten last night I ___ (sleep).
3. She ___ (know) the answer straight away.
4. While he ___ (cook), the children ___ (play) outside.
5. I ___ (drop) my keys and ___ (not see) where they went.

Answers: 1. were walking ... started (the long action is the walk) 2. was sleeping 3. knew (know is a state verb, so no continuous) 4. was cooking ... were playing (two long actions at once) 5. dropped ... did not see (both are short finished events, so both are past simple)