I took a test on articles and scored 84%. Unfortunately, the site provides no explanation as to why I was wrong, so I kindly ask for your help here.
Kumiko discovered that there were quite a few cultural differences between the Danish and Norwegians. She had always assumed Scandinavians were the same.
I used 'the Scandinavians' instead of 'Scandinavians' because I though it was referring to a class. Can anybody explain why, unlike 'the Danish and Norwegians', there should be no article?
Thanks for all your help. What helped the most was the thread at http://forum.wordreference.com/threads/definite-article-with-nationalities.1021920/—especially, this part: https://i.stack.imgur.com/CmT5A.jpg.