呃...这个问题在不同句型中,又不一样的答案,在宾语从句中较好判断,就说在定语从句中的吧~~
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在定语从句中
1、关系代词：who, whom, which, that, whose
指人：who, whom, whose, that
指物：which, that,whose
2、关系副词：when,where,why
作主语,先行词是人用who/that
先行词是物用which/that
eg.一个男孩a boy
一个能讲三国语言的男孩the boy who/that can speak three foreign languages
一扇门a door
一扇木制的门the door which/taht is made of wood
作宾语,先行词是人用whom/that(who)
先行词是物用which/that
eg.一个女孩a girl
一个警察正在找的女孩the girl whom/that the police are looking for
一把钥匙a key
一把我昨天弄丢了的钥匙the key which/that I lost yesterday
whose 作定语,先行词可以使人,也可以是物,形式为whose + n.
一位学生a student
一位母亲生病的学生the student whose mother is ill
一个房子a house
一个窗子面朝南的房子the house whose windows face south
eg.I saw a tree. Its leaves were black.
→I saw a tree whose leaves were black.
=I saw a tree of which the leaves were black.
先行词指人：
whose + n. =the + n.+ of whom(或of whom + the + n.)
先行词指物：
whose + n. =the + n.+ of which（或of which.+ the + n.)
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呼~打得好辛苦!可怜的打字速度...
以上内容不是搜索来的,准确率蛮高,可以放心用,若要深究只能用that、只能用which...还有好多内容...