Ten obligations in 三字经 Here's the final excerpt from part one of 三字经 [1]:


  父子恩 夫婦從  兄則友  弟則恭  長幼序  友與朋 君則敬  臣則忠  此十義  人所同


Simplified Chinese:


  父子恩  夫妇从  兄则友  弟则恭  长幼序  友与朋 君则敬  臣则忠  此十义  人所同


Translation [2]:


  Kindness between father and child,
  
  harmony between husband and wife,
  
  friendliness from elder brothers,
  
  respect from younger brothers.
  
  Precedence between elders and youngers,
  
  support between friends,
  
  Respect from the sovereigns,
  
  loyalty from the subjects.
  
  These ten obligations are the same for all.


I count only eight obligations in this excerpt. Where, then, are the remaining two that the autor of the poem speaks of?

[1] http://www.dfg.cn/gb/zhhy/whdc/04-sanzijin.htm

[2] https://www.yellowbridge.com/onlinelit/sanzijing.php
the trimetrical classic (三字經) is extracted from ancient confucianism literatures, in three characters verses.

the eight verses in question are derived from 禮記　禮運


  父慈．子孝．兄良．弟弟．夫義．婦聽．長惠．幼順．君仁．臣忠十者．謂之人義


if you've some knowledge of confucianism, you can find components of 五倫 from these eight verses:


  君臣．父子．兄弟．夫妻．朋友


each one of these have two "人義"; so five of them makes ten "人義".

have fun :)