"I have drunk coffee Monday."

Translation: Dw i wedi yfed coffi dydd Llun.

[Anneke69]

Why are both 'dydd' and 'ddydd' accepted?

[MarrriiiiO]

I too wondered why?

[StephenDunscombe]

Do we not mutate "dydd Llun" to "ddydd Llun" when we use it as a prepositional phrase?

[GarethBurk]

It mutates after "ar"

[GarethBurk]

If it had said "on Monday"