It is impossible to defeat a person who never gives up.象这样的不定式做真正主语的,比如这句里面他的真正主语是 to defeat 还是整个 to defeat a person?如果只是前面的,那后面的a person是什么成分?

It is impossible to defeat a person who never gives up.
象这样的不定式做真正主语的,比如这句里面
他的真正主语是 to defeat 还是整个 to defeat a person?
如果只是前面的,那后面的a person是什么成分?

后面a person 当然是defeat 的宾语了

to defeat a person (定语从句who never gives up) 合起来作主语

调一下语序：to defeat a person (who never gives up)主+is(谓）+impossible(宾）
这种句型就是为避免“头重脚轻”的特殊句式