定语从句whose和whose of which用法

定语从句whose和whose of which用法
我知道whose指人 whose of which指物但 They rushed over to help the man whose car had broken down.那人车坏了,怎么知道那上面例句为什么不用who that 而用whose 呢 而Please pass me the book of which color is green.请递给我那本绿皮的书.为什么不用that呢