无牙颌模型边缘应有一定的宽度，一般宽为（）。
A.1～2mm
B.2～3mm
C.3～4mm
D.4～5mm
E.5～6mm
参考答案：C
There are in a season.[ ]
A. three years
B. three months
C. three weeks
D. three month
After all, the candidate was endorsed by the governor's board and many of the local party members.
A．sponsored
B．approbated
C．recognized
D．rejected
