Stand-up comedian Henning Wehn takes over a German class ... additional German letters in the alphabet, the ß, ä, ü and ö. Where would Düsseldorf be without its umlaut?

How does the umlaut change the pronunciation of u in German? Focus on the [y] j phoneme in 'Jakob', 'Jens'. Support understanding of grammar by highlighting capital letters for nouns, for example ...