问题补充:
The time I first spend with Nelson Mandela was a very difficult period of my life.
Awhen
Bwhich
Cof which
Dat which
答案:
A. when
(答案→)B. which
C. of which
D. at which
解析:句意:我第一次和曼德拉度过的时光是我生命中非常困难的一段时期。这个句子包含一个定语从句,且关系词在从句中作宾语,指物,故用关系代词 which,选B。