Martin had become Howard Cosell's surrogate son.是什么意思？

Martin had become Howard Cosell's surrogate son.

马丁代为当起了霍华德·科塞尔的儿子。

martin

n. 燕科小鸟（如岩燕、雨燕）；

例句
The plot to assassinate Martin Luther King had started long before he was actually killed.
刺杀马丁·路德·金的计划在实施前酝酿已久。

had

v. 有（ have的过去式和过去分词 ），（亲属关系中）接受，拿，买到；

例句
He claimed that his parents had abandoned him...
他声称父母遗弃了他。

become

vi. 变为，成为，变得，变成；vt. 适合，适宜，相称，相当，变成，发生；

例句
...abandoned buildings that become a breeding ground for crime.
沦为了犯罪温床的弃置楼群

Howard

n. 霍华德（男子名）；

例句
The film was directed by Howard Hawks.
该影片是由霍华德·霍克斯导演的。

surrogate

n. 代理，代表，代用品，代替，代孕者，[心]代用人物，〈美〉遗嘱检验法庭[法官]；adj. 代理的，代理的；v. 代理，替代；

例句
Martin had become Howard Cosell's surrogate son...
马丁代为当起了霍华德·科塞尔的儿子。

son

n. 儿子，孩子，男性后裔，圣子（耶稣基督）；

例句
In the name of the Father and of the Son and of the Holy Ghost, Amen.
以圣父、圣子和圣灵的名义，阿门。