英语句型转换,同义句~

题目

英语句型转换,同义句~
As the child at six,he began to play the piano.(同义句）
______ ______ ______ ______ ______ ______,he began to play the piano.
我是这样写的：At the child"s age of six 行不行?
(答案给的是When he was six years old)

答案

当然还是答案正确了,开始我想的是：When the child was six years old,不过差一个空,把the child 改成he也是可以的.