充填塑料过程中常见的问题是（）
A.产生气泡
B.支架移位
C.咬合增高
D.基托颜色不一
E.牙冠和基托塑料连接不牢
参考答案：A, B, C, D, E
The college entrance exam is ______ important to the student, and it’s also challenging.
A．no more than
B．no less than
C．more than
D．not more than
立面图的形成，就是（）
