used for introducing a situation that may happen or may be real, especially when talking about its results
If we miss the last bus, we’ll have to walk home.
If anyone has found a bunch of keys, would they please leave them on my desk.
if you want/like: You can come and stay with us if you want.
if so (=if this is true): Are you planning to return to work, and if so, who is going to look after the baby?
if not (=if this is not true): Has anyone dealt with the technical problems? And if not, why not?
if necessary/if possible (=if it is necessary/possible): We are ready to fight for our rights if necessary.
I should like to be back here by 10.30 if possible.
Synonyms and related words