"The boy takes the red stone from the mirror."
Translation:Gutten tar den røde steinen fra speilet.
My thought (and i might be wrong), and at least the way that I have thought about it so far, is that with the adjective there, you are that much further away from seeing that it is a definite form when the 'et' or 'en', etc. is at the end of the phrase.
But my thinking could also be clouded because English puts the definite article at the front.