on the way back to the hotel中back to the hotel是什么成分？back是什么词性？

on the way back to the hotel中back to the hotel是什么成分？back是什么词性？

on the way back to the hotel中back to the hotel是副词短语，在句中做状语；back为副词，意思是：返回、回来。例如：
　　1、I went back to bed.
　　我回到床上。

　　2、I'm due back in London by late afternoon.
　　我预计下午晚些时候回到伦敦。

　　3、Smith changed his mind and moved back home.
　　史密斯改变主意，搬回家了。

　　4、I'll be back as soon as I can.
　　我会尽快回来。