矫治前必须有记录患者牙牙合情况的模型，称之为
A．石膏模型B．记存模型C．初模型D．上颌模型E．终模型
参考答案：B
The film directed by Zhang Yimou is beyond praise and it has certainly ______ my expectations.[ ]
A. led to
B. taken to
C. lived up to
D. agreed to
GPON是基于（）。
A．ATM封装
B．以太网封装
C．GEM封装
D．ATM、GEM封装
