Is this an actual welsh construction or a structured borrowed/inherited from English? "Going to" is a typical English construction for the future, I'm wondering whether it's a construction native the welsh if anyone knows?
That's a very interesting question. A little search in the online dictionary of the University of Wales shows reference to this form back to the 13th century, so it's probably older in Welsh than in English.
Like Alice initially said, the grammatical similarity between this sentence and its English equivalent is striking.
I wonder if this goes deeper, maybe the britions who adopted Anglo-Saxon dialects incorporated British Celtic influences into their version of the still forming early English language, in the same way French seems to be a Latin language with Celtic influences? Just an idea.