I did an online test on Korean language provided by NHK Japan (in Japanese).
I studied everything I missed the first time (for example, I was completely clueless about -러 불규칙 and didn’t know how to pronounce 밟다) and on my second try, of course I got perfect score.
And then, I got a list of Korean textbooks published by NHK recommended for my level. Hahaha. Good marketing.
Maybe I can ask my husband to get one for me when he goes to Japan on business next month. ###