when · adverb /wen/Full view
A1 used to ask at what time something happened or will happen
Dictionary examples:

"I did tell you about it." "When? I don't remember."

When's your birthday?

When did he leave?

Learner example:

When are you coming [to] my house? (Key English Test; A2; Japanese)

when · conjunction /wen/
A2 used to say at what time something happened or will happen
Dictionary examples:

I found it when I was cleaning out the cupboards.

We'll go when you're ready.

She was only twenty when she had her first baby.

He was quite shocked when I told him.

Learner example:

I'll ring you when I arrive. (Key English Test; A2; Spanish)

B2 used to say something that is surprising after what has already been said
Dictionary examples:

He says he hasn't got any money when in fact he's got thousands of dollars in his account.

I don't understand how he can say that everything's fine when it's so obvious that it's not.

Why is she training to be a teacher when she doesn't even like children?

How can you say you don't like something when you've never even tried it!

Learner example:

In your advertisement it was said that I would find stars and artists from around the world, when, in fact, they were from only six countries. (First Certificate in English; B2; Spanish)

when it comes to sth/doing sth
C1 used to introduce a new idea that you want to say something about
Dictionary example:

When it comes to baking cakes, she's an expert.

Learner example:

But when it comes to computers, they just impose some knowledge on students, without any interaction. (International English Language Testing System; C1; Chinese)

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