PHP Help

[[D]Vincent]

I'm new to PHP and don't know much about it, but I'm trying to make a rpg class hack for my forums. This of course would be simple, but I'm making it to where they select a class in User CP and level up in it, so I was wondering how to make something equal something with two if's. Like I need it to be if $rpgclass equals Squire and $shwolevel equals 3 through 7 then it will equal something else like Knight or something. I would have just created multipule post fields and did it like
If ($showlevel == 3)
{
$post[fieldwhatever] = Knight
}
But then I have the porblem with postbit of getting them all into and I still don't know how to make it equal that level to another level. Can someone help?