"When were you born?"
Translation:Pryd cest ti dy eni?
gaethoch is a mutated form of caethoch - the g- would not be dropped because you can't mutate a word twice over.
To be strictly correct, there should in any case be no mutation after pryd?, ble/lle?, pam?, sut? (how?):
- Pryd caethoch chi'ch geni
- Pryd cest ti dy eni?
- Sut roedd y cyfarfod?
- Pam rwyt ti wedi symud i Bont-y-pŵl?
But in the informal registers of the language, people very often do mutate after pryd in particular. In this course, the mutated forms after pryd...? are accepted.