Frank was telling me about his experences as a young man.的句子成份?as做什么词,起何作用?

Frank was telling me about his experences as a young man.的句子成份?as做什么词,起何作用?
Frank （主语） was telling （谓语） me（直接宾语） about his experences as a young man（介词短语作间接宾语,）.
about his experences as a young man -- 如何细分句子成份?
as a young man 是定语修饰experence,但是什么句型？