"Before the petrol finished, I went to the garage."
Translation:Cyn i'r petrol orffen, es i i'r garej.
I'd never heard of modurdy before this translation came up. It's certainly not in the "Oxford Pocket Modern Welsh Dictionary" by Gareth King which is used by many learners, so I'd agree that it seems to be archaic. I do, however, like how it came about (Thanks Balbhan!), and do actually like it better than the English import, however, in trying to learn to speak the language, I'll stick to the latter as I guess I'll be understood better (and that's my aim!)