Simplify the following text for a Grade 10 native English-speaking person.
Original: In contrast to the black-uniformed Allgemeine SS ( the political wing of the SS ) , the Waffen-SS ( the military wing ) evolved into a second German army aside the Wehrmacht ( the regular national armed forces ) and operating in tandem with them ; especially with the Heer ( German Army ) .
Simplified: In contrast to the black-uniformed Allgemeine-SS , which was the political wing of the SS , the military wing was called the Waffen-SS , which evolved into a second German army within the Wehrmacht . It worked in tandem with the regular German army , or Heer .