英语语法求解释Few of the cultural traditions and rules that today a

Few of the cultural traditions and rules为主语,that today allow us to deal with dense populations是定语从句,修饰the cultural traditions and rules,existed是谓语,for these people是状语,
accustomed to household autonomy and the ability to move around the landscape almost at will是定语,修饰people,其中household autonomy and the ability to move around the landscape almost at will是介词to的并列宾语

that是主语从句的引导词，today是时间状语that是主语从句的引导词的话 那that后面的应该是主语啊 。。。。。。。但是that在主语后面又不充当成分，貌似没见过这种主语从句。。。that在这里可以充当主语从句的主语名词性从句that可以充当成分？ 没听说过 给个例子？...

不是，我觉得应该是定语

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