刘老师上次解答内容部分转载如下：

5. He stands before this youth who is ten years junior to him. =

6. He stands before this youth ten years junior to him.  

他站在这个比他小十岁的青年面前。

句6， 省略 who is 后，由定语从句变成形容词短语作定语。

7. He stands before this youth who is ten years his junior. =

8. He stands before this youth ten years his junior. 

他站在这个比他小十岁的青年面前。

句8，省略 who is 后，由定语从句变成形容词短语作定语。

ten years his junior是名词短语，应该是同位语。刘老师说为形容词短语作定语是笔误把。