可视电话与pstn电话的相同点有？（）
A.语音电话
B.屏幕分辨率
C.摄像头
D.喇叭
参考答案：A
I noticed them the teachers' office just now. [ ]
A. went into
B. go into
C. was going into
D. came out of
牙体预备不当引起牙髓最严重的损伤是
A．牙髓激惹
B．牙髓变性
C．牙髓坏死
D．急性牙髓炎
E．慢性牙髓炎
