I recently discovered a great online flashcard site, Cerego. I have a memory problem, and coupled with all the extra Welsh vowels, and apparently more vocabulary in this course than other Duolingo courses, well I have difficulty remembering all the words. So I added some to Cerego. If they are useful to anybody else feel free to use them. When signed up use the search feature to look for “Welsh” and you should find them.

https://cerego.com/search?utf8=✓=Welsh