355163
Both his grandfather Duan Da ( 段達 ) and father Duan Xingchen ( 段行琛 ) served as military officers .
 Duan, Duan
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Duan, Duan