when
whenadverb
UK/wen/US/wen/
QUESTION
A1used to ask at what time something happens
- When is your birthday?
- When did you arrive?
AT WHICH
B1at which time
- Do you remember the day when we first met?
whenconjunction
UK/wen/US/wen/
AT THE TIME
A1at the time that something happens
- I lived in Spain when I was a child.
- Call me when you get home.
ALTHOUGH
B1although, or considering that
- Why do you take the car when you could walk?