or · conjunction /ɔːr/Full view
A1 used between possibilities, or before the last in a list of possibilities
Dictionary examples:

Would you like tea or coffee?

Is that a boy or a girl?

You can have beer, wine or mineral water.

It was either 1982 or 1983 - I can't remember which.

There were ten or twelve people in the room.

It will only take three or four days.

Learner example:

I like to eat pasta or pizza, but I'm easy about food, I can eat anything. (Skills for Life (Entry 1); A1; French)

A2 used after a negative verb to mean not one thing and also not another
Dictionary examples:

Tim doesn't eat meat or fish.

She doesn't have a telephone or a computer.

Learner example:

OH! and please don't wear jeans or white clothes. (Key English Test; A2; Thai)

or not
A2 used to express the possibility that something might not happen
Dictionary examples:

Are you going to reply or not?

I still don't know whether she's coming or not.

Learner example:

Are [you] busy or not that day? (Key English Test; A2; Singhalese)

B1 used to give someone a warning or advice
Dictionary example:

You should eat more, or you'll get sick.

Learner example:

She called "Bill, come here or you'll be in trouble". (Preliminary English Test; B1; Farsi)

B2 used to change or correct something you have said
Dictionary examples:

We told the truth, or most of it.

Eleanor, or Ellie to her friends, took the initiative.

Things have been going well recently. Or they were, up until two days ago.

Learner example:

She is the one [who goes] around with all Rebecca's secrets. Or, almost all the secrets. (First Certificate in English; B2; Danish)

or so
B1 approximately
Dictionary example:

I think we raised five hundred dollars or so for the charity.

Learner example:

Well you told me about your situation and after thinking a lot I thought you should go with them for a week or so, and then just take a plane and come to Barcelona to visit me. (Preliminary English Test; B1; Catalan)

or else
B2 used to say what will happen if another thing does not happen
Dictionary example:

We have to be there by six, or else we'll miss the beginning.

Learner example:

[He] told me to hurry up, or else I would miss my bus. (First Certificate in English; B2; Portuguese)

C2 used to give a reason for, explain, or correct something you have said
Dictionary examples:

Things were going well, or seemed to be, but the relationship had already begun to change.

She must love her work or she wouldn't have kept at it all these years.

Learner example:

I [have] stud[ied] music since I was twelve or, in other words, I started to learn how to read music and how to play an instrument about ten years ago. (Certificate of Proficiency in English; C2; Catalan)

or two
B1 used to indicate a very small number, often no more than two
Dictionary examples:

We will spend a day or two in Boston.

Mom said I can bring a friend or two with me.

I'd like to ask our guest of honor to say a word or two.

Learner example:

The thing you can do, is go out with your family first and than with your friends, or, you can ask your parents, if you can invite a friend or two to go with you. (Preliminary English Test; B1; Spanish)

or other
C1 used when you cannot or do not want to be exact about the information you are giving
Dictionary examples:

The event was held in some park or other.

We'll find someone or other to help us.

Learner example:

Maybe you hate the memory of boring literature classes at school, but I'm sure each of you is interested in some subject or other. (Certificate in Advanced English; C1; Spanish)

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