when

Definitions

1. adverb

   Used to ask what time something happens.

   Examples

   • When will they arrive?
   • Do you know when they arrived?
2. conjunction

   Used to say that something always happens at certain times, like every time that.

   Examples

   • Dogs bark when they hear a noise.
   • When he speaks to her, he is always polite.
   ≈as soon as≈immediately≈once≈whenever≈whenever
3. conjunction

   During the time that something else is happening.

   Examples

   • They dream when they sleep.
   • I'm happiest when I'm working.
   ≈while
4. adverb

   Used after a time word to mean at which or during which.

   Examples

   • That was the day when we met.
   • Not a week goes by when I don't think of her.
5. adverb

   The time at which something happens.

   Examples

   • I remember when they were called the Greys.
   • Next year is when we choose a new mayor.
6. adverb

   A situation in which something is true.

   Examples

   • Love is when you can't get enough of someone.
   • Success is when preparation meets opportunity.
7. adverb

   Used after a word to ask impatiently about the time of something.

   Examples

   • The site is broken. Fix when?
   • New season when?
8. adverb

   At an earlier time when things were different.

   Examples

   • He is rich now, but I remember him when he had nothing.
   • She talks about the good old days, back when.
9. conjunction

   Used to say at which time something happens next.

   Examples

   • I am here until Friday, when I leave for Senegal.
   • I was walking down the street, when suddenly it started to rain.
10. conjunction

    Used to mean since or considering that.

    Examples

    • I don't see the point of putting up decorations when I am the only one who will see them.
    • Why complain when you knew the risks?
    ≈given that