单侧垫活动矫治器的适应症是（）
A.单侧后牙正、反锁或反
B.前牙反
C.牙列拥挤
D.安氏Ⅱ类错
E.深覆、深覆盖
参考答案：A
It is known that ________ medical examination helps people to find out health problems as early as possible.
A．normal
B．general
C．regular
D．common
住房短缺
