This is the 5714th most frequent German word.
bonn
"Bonn" is a city in Germany.
Here, 'Bonn' is used as a proper noun referring to the city of Bonn in Germany.
Bonn ist eine schöne Stadt mit vielen Sehenswürdigkeiten.
Bonn is a beautiful city with many sights.
The word 'Bonn' again acts as a proper noun, specifying the location where the event of studying occurred.
Ich habe in Bonn studiert und viele Freunde dort gefunden.
I studied in Bonn and made many friends there.
Here, 'Bonn' identifies the birthplace of the renowned composer Beethoven, used as a proper noun referring to the city.