关于南北极地区极夜持续时间的叙述正确的是( ) A.北极极夜持续的天数多于南极地区 B.北极地区极夜的持续天数与南极地区相等 C.北极极夜持续的天数少于南极地区 D.北极地区极夜的持续天数比南极地区有时多有时少 答案:C 解析: 略18、Alice won’t want to eat it
unless she is really hungry, _______ she’ll eat almost
anything.
A.for
which
B.in which
case C.in that
case D.in which