With an appropriate relative pronoun or relative adverb:
(1)This is the best biography ____ I have read of Churchill. (2)He is straight A student, ____ his brother never was.
【正确答案】：that; which
【题目解析】：本题考查定语从句的关系代词要点透析】当先行项前有 the best等修饰时,关系代词用that;第二句中, which引导非限制性定语从句,指代前面主句内容。
