当先行词是物的时候关系代词用that 或者which,但是当这个先行词在从句中做宾语,也可以用which

1、关系代词that指代“人、物”,which则只能指代“物”,所以当先行词是【物】的时候,关系代词即可以用which也可以用that.比如：
The package (which / that) you are carrying is about to come unwrapped. 你拿那个包裹快要散开了.
2、但是如果先行词是指代【人】时,则用that或者who.比如：
The boys who/that are playing football are from Class One.
3、关系代词在定语从句中可以充当句子的【主语】、【宾语】,作定语从句的主语时不能省略,但是作定语从句的【宾语】时可以省略.比如：
(1) Is he the man who/that wants to see you? 他就是想见你的人吗?（who/that在从句中作主语,不是省略）
(2) He is the man whom/ that I saw yesterday. 他就是我昨天见的那个人.（whom/that在从句中作宾语,可以省略）
4、Reben is a group ___many people love very much.
这个句子中group指代是一个“组合”,是指代人,所以我觉得用that,而不能用which,当然that也可以省略.句意是：Reben是很多人都非常喜欢的一个组合.