问题补充：
He was old music write started was when he was这道题错在哪里?要写出因为所以
答案：
He was an old music writer who started his career when he was 10 years old.
主语He 谓语was 宾语 an old music writer 定语从句 who started his career when he was 10 years old.
======以下答案可供参考======
供参考答案1:
同意一楼的观点
