as far as I can see, the translation that is given is 'you drink', which is correct. It can also be 'you are drinking'
It looks to me like "nywa" is treated like a single syllable, hence including "ku" here, as well as putting the spoken emphasis on "ku" (as the penultimate syllable) in something like "Anakunywa". Maybe someone can confirm if my impression is right? :-)