选择人工前牙时不必考虑的因素
A．余留牙的颜色、形状和大小B．患者过去是否戴过义齿C．患者的面型D．患者的肤色E．患者的年龄
参考答案：B
There is a new problem involved in the popularity of private cars ________ road conditions need ________.
A．that；to be improved
B．which; to be improved
C．where；improving
D．when；improving
为什么库房应设有防静电设施？
