when / if

[ofriendragon]

hi, guys

My dictionary tells me that when equals if sometimes, could you please tell me what's the difference between them?

Thank you in advance.

 

[Mike]

A bit of a kneejerk reaction here, but I'd say that when we use when, there is more of a certainty that something will happen.

E.g. When you go to the party, call me.

This means the speaker is certain that the other person will go to the party.

If you go to the party, call me.

This means that the speaker is not 100 percent sure the other person will go to the party, but if the other person does go to the party, he would like that other person to call him.


Does that help at all?

Mike

 

[panjandrum]

They are different in that:
when generally identifies a time;
if does not, necessarily.

When I get home from work - implies that I will get home from work.
If I get home from work - implies that I might not.

Does your dictionary give examples of when = if?

 

[Mike]

So I guess when expresses certainty and if expresses possibility.

 

[Mike]

And yeah, when expresses time, as well. Should have put that in there... one of its main functions really...