1.先行词是人，且在从句中作主语时，用关系代词who/that；在从句中作宾语时，用whom/who/that, 或者省略。
Eg. The man who/that lives in that house is my uncle.
That is the girl（who/whom/that）I met at the party yesterday（先行词作宾语）.
2. 先行词是物，可用关系代词which/that充当从句中的主语和宾语，作宾语时可以省略。Which除了指物以外，还可以婴儿、动物和表示单数意义的集合名词，此外还可以指人的属性，如身份、地位、职业或品格等。
E.g. My favorite place is Kunming which/that is called as the Spring City.（从句是主谓宾结构call后不能直接加宾语，春城是宾语，先行词是主语）
This is the place (which/that) he would like to visit. （feel like doing三个想要做某事）
The audience（集合名词：单数表一群人） which is composed entirely of（由...组成） students is larger than ever. （修饰比较级的词两多much a lot;两少a little a few一远去far；一甚至even）
Eg. The man who/that lives in that house is my uncle.
That is the girl（who/whom/that）I met at the party yesterday（先行词作宾语）.
2. 先行词是物，可用关系代词which/that充当从句中的主语和宾语，作宾语时可以省略。Which除了指物以外，还可以婴儿、动物和表示单数意义的集合名词，此外还可以指人的属性，如身份、地位、职业或品格等。
E.g. My favorite place is Kunming which/that is called as the Spring City.（从句是主谓宾结构call后不能直接加宾语，春城是宾语，先行词是主语）
This is the place (which/that) he would like to visit. （feel like doing三个想要做某事）
The audience（集合名词：单数表一群人） which is composed entirely of（由...组成） students is larger than ever. （修饰比较级的词两多much a lot;两少a little a few一远去far；一甚至even）
