在罩牙本质和透明层内侧的牙本质（）
A.修复性牙本质
B.球间牙本质
C.髓周牙本质
D.托姆斯颗粒层
E.前期牙本质
参考答案：C
When this boy was asked to copy down the sentence ten times, he did nothing but _____deeply with a blank look on his face.
A．sigh
B．sight
C．sign
D．signal
小物件卡阻处理时，小物件或卡子不多时，可试用震击解卡。
