Useful English: 18. Occassionally 19. Once in a while

occassionally: * sometimes, but not regularly and not often

I occassionally go out to eat Okokomiyaki ("Japanese Pizza").
My father occassionally cooks.

once in a while:* sometimes, although not often

I wish you`d ask me out once in a while.
We should make it a rule to go for a walk together once in a while.