I can’t remember _______ you started doing the work.

A．that it was when

B．when it was that

C．when was it that

D．that was it when

该图为某地人口迁移数量与年龄关系示意图。读图完成问题。

小题1:从图中判断,影响该地区人口迁移的主要因素最可能是

A．人口老龄化

B．婚姻家庭

C．政治因素

D．经济因素小题2:图中甲、乙、丙、丁不同年龄段的人口迁移，有明显相关的是

A．甲、乙

B．甲、丙

C．乙、丙

D．乙、丁