sentences:  Morris Mack died at the age of 78 on August 14, 2017.Of the nine schools, or Kwan's (Kan) that merged to form Taekwondo, four of those schools have lineages that trace back to Toyama Sensei through three Korean men who trained in Japan while Korea was under Japanese occupation.These three men were Kim Ki Whang, Dr. Yoon Kwey Byung and Yoon Byung In.