the descriptions given by people中 by是 介词短语做后置定语吗?

问题描述:

the descriptions given by people中 by是 介词短语做后置定语吗?
the descriptions given by people中 by people是 介词短语做后置定语吗?我只知道given是做定语的.他们不是相连的吧?分开的2个介词短语?还是过去分词做被动语态 by是被动语态的by?

过去分词做被动语态 by是被动语态的by