Grrr, I put "have you got a cat?" and it was marked incorrect! No-one says "have you got cat?" Minor glitch
Well actually I say "have" rather than "got".
What's the difference between "gynnoch chi" and "gyda chi"?
Have another look at the tips and notes for the Possession lesson: https://www.duolingo.com/skill/cy/Possession
(Short version: no difference in meaning)
Thought as much, will report in future if marked incorrect for using one over the other.
I answered with "Do you've a cat" and it was marked as correct - this isn't right IIRC.
A generic Duo fault at the moment. Please report it in the general Troubleshooting forums- the more reports that people make there, the quicker they may fix it.