会导致咀嚼无力的是
A．基托边缘过长或过锐 B．基托变形 C．基托与黏膜不密合 D．人工后牙覆盖过小 E．垂直距离过低
参考答案：E
--- I have _____________, I’m afraid I have to see the doctor.
--- I ‘m sorry to hear that.
A．a good eyesight
B．good eyesight
C．a poor eyesight
D．poor eyesight
调整垫铁一般用于精度要求不太高的设备的安装中。
