"A good suit"
Siwt is a feminine noun, as explained in the notes. Feminine nouns cause changes at the start of following adjectives - in this case, da changes to dda. This explained in more detail later in the course.
Siwt da, which sometimes appears at the moment, is incorrect and will be deleted from the course.
This was eight months ago and this, and many other errors are still in the course. Is this actually being worked on?
There are in fact very few errors left in the original course, due to the dedication of the volunteers who work on corrections and responding in the forum.
Personally up to now I have added 14,000 sentences to the course as well as responded to many, many thousands of reports, which these days are mostly wrong.
My contribition, if you look on the course page, is only 30% of the total, thus you can get an idea of the work being done by the unpaid, voluntary contributors.
In addition we have been working on the second course making many changes to extend the learning experience. Due to the extremely clumsy Duolingo editor, something that was supposed to be completed in 3 months is still months away from finishing.
The Welsh course is one of the few crowd sourced courses on Duolingo where there is continous development.
I'm sorry if my comment came across as overly aggressive, I didn't mean for it to be like that but having re-read it, it certainly does.
Thanks for the reply, I, along with many others I'm sure, appreciate the hard work and dedication of the team.