关于分词做伴随状语和后置定语的问题

伴随状语相当于两个独立句子。
She held several records, earning them when she was 7. =She held several records.① She earned them when she was 7②
I wrote the sang, inspired by Kim. =I wrote the sang.① I was inspired by Kim②
后置定语相当于定语从句，可以还原为that/which/who等引导的形式，修饰前面的某个名词。是一个句子。
There were some children swimming in the river. = There were some children who were swimming in the river.
She held speed records, earning them at a time that aviation was so new. 这是一个现在分词，是主动语态，说明两个动作主语相同，很明显属于伴随状语，可以拆分为独立的两个句子：She held speed records① She earned them at a time that aviation was so new②
She held speed records, earned at a time that aviation was so new. 这是一个过去分词，表被动语态，很明显是在说recoreds，因为只有records才能be earned，是主语she来earn这个recoreds。是后置定语，相当于She held speed records which were earned at a time that aviation was so new.
逗号和定语/状语没有绝对的对应关系，不能用逗号作为判断是定语还是状语的依据。

非谓语东子作为修饰语，如果过长，可以逗号将它与被修饰的部分隔开；如果短小精悍，直接和被修饰的部分连接，不用标点隔开。