A:used to live; are used to living
B:are used to living; used to live
C:used to live; used to live
D:used living; used to living
—Certainly.But you can't it to others.
1921年,苏俄实行的新经济政策( )
在①小孔成像;②平面镜成像;③放大镜成像;④照相机成像;⑤幻灯机成像中( )