Question

In the cafeteria, I saw my sister and her three friends, none of ____ I had ever seen before.

A．them

B．which

C．whom

D．those

Answer 1

C

试题分析：考察定语从句。本题定语从句的先行词是my sister and her three friends，关系代词whom指代先行词my sister and her three friends作为介词of的宾语。因为先行词是人，且作为宾语，故使用whom。AD两项不能引导定语从句，which的先行词是物。故C正确。
点评：定语从句的考查主要就是考查关系词的辨析，关系代词that, which, whose, whom, as， who在句中做主语，宾语，表语或者定语；where, why, when在句中做状语。要分析句子成分，看缺少什么成分，就选用相应的关系词。