I was given three books on cooking, the first I really enjoyed.
A. of that
B. of which
C. that
D. which
网友回答
A. of that
(答案→)B. of which
C. that
D. which
解析：这道题容易误选C. that，因为当先行词被形容词最高级或the first和the last修饰时定语从句的关系词用that而不用which，一看见有the first (book)就匆忙选that。其实从句的先行词是three books而不是the first (book), the first (book)是从句的内容。这是个非限制定语从句，所以应选B. of which， the first of which=the first of three books。