What does if mean?
if
Definition
A clause-linking grammatical marker that takes a stated or assumed proposition as the premise for a response, recommendation, or intention, without requiring the premise event to happen before the response action.
Example sentences
If you're going to Japan, you should buy a train ticket before you leave.
If you're going to Japan, you should buy a train ticket before you leave.
If you're coming tomorrow, I'll make lunch.
If you're a student, please show your student card.