灌封中可能出现的问题是
A．药物水解
B．焦头
C．鼓泡
D．剂量不准确
E．封口不严
参考答案：B,C,D,E
With the world _____ fast, we have something new to deal with all by ourselves every day.
A．change
B．changed
C．tochange
D．changing
摩擦片不得有（）。
A.裂纹、破损、烧焦
B.磨损、破损、烧焦
C.裂纹、磨痕、烧焦
D.裂纹、破损、瑕疵
