"You do not have to say."
Translation:Does dim rhaid i ti ddweud.
Paid â dweud dim byd wrth Dewi. - Don't tell Dewi anything! (A command)
Does dim rhaid i ti ddweud dim byd wrth Dewi. - You don't have to tell Dewi anything. (A statement)
Wyt ti'n mynd i ddweud wrth Dewi neu beidio? - Are you going to tell Dewi or not?
No, it's a common dialect variation that we need to have in the course as an alternative form as it is taught on some Welsh courses in Wales. It would be better if Duo didn't put it up as a general correction, but as a team we cannot control the system's choices. I have just changed how it appears in the database and that might perhaps help Duo to pick the common form of dweud, but it is hard to tell.