Well, taking easy. The both are right to say. Therefore, 'keif halak?" is an expression using in an accent in Arabic. The second one, it's MSA. (Modern Standard Arabic). I think, you're about to start with Arabic. Take a look to this document I've created for people who just start with Arabic. Hope it's helpful for you. https://drive.google.com/file/d/0BzvhBAGutWs5bEZFbGhEbUZfaDg/edit?usp=sharing Salam

Keif haluka (how are you to male) keif haluki ( = = = = female) keif halukma( = = = = 2 person) keif halukum( = = = = 3 person and up male) keif halukune( = = = = 3 person and up female)