what's gone is gone.It's no use talking about it any more.

问题描述:

what's gone is gone.It's no use talking about it any more.
请帮我分析一下前半句的结构和意思.

过去的都过去了,再多想它也无用.
what has gone——表示“已经过去的事情”,在句子里做主语,然后是is gone.