【题目】They will never forget the days _______ they spent together studying abroad.
A.in whichB.thatC.on whichD.during which
在线课程【答案】B
【解析】
考查定语从句。句意：他们永远忘不了他们一起在国外学习的日子。分析句子可知，_______ they spent together studying abroad是定语从句，修饰先行词the days；先行词在从句中做spent的宾语，用关系代词that\which。故选B。