I'm really confused. Why can't Billy Change into a wolf?

billy cant change into a serigala, wolf because if anda can control your anger for a certain amount of time and not change into a werewolf then anda cant change anymore.

no its because the serigala, wolf genes skipped his generation because the Vampires werent in forks yet.

Because he has decided it. He doesn't want to convert in a serigala, wolf anymore.

The werewolf gene did skip his generation.

Billy can't change into a serigala, wolf because it skipped a generation so if Jacob had a kid he/she couldn't change into a werewolve but thier kid could!!!

because he tribe is decended from the serigala, wolf he not a wolf.