"I eat the rice."
Translation:Jeg spiser risene.
So I'm guessing with the definite form, rice is considered plural because you're probably eating more than one and singular with the indefinite?
Ris is almost always plural. If you want to talk about one piece of rice you could use "et riskorn" (a rice seed)
So then, I'd gather that "risen" would be used very sparingly, and that "risene" what be the more typical form. Or, are they more or less interchangeable.