会导致食物嵌塞的是
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：C
Oct. 1st, ____ is our National Day, is celebrated with singing and dancing. [ ]
A. which
B. as
C. when
D. that
保险营销以( )为导向。
A．保险人 B．消费者 C．投保人 D．保险代理人
