槽液中的固体分高可能导致的电泳缺陷是（）
A.膜厚偏低
B.膜厚偏厚
C.涂面斑印
D.二次流痕
参考答案：B
As I know, there is __________ in this school.
A．no such student
B．not such a student
C．no such students
D．not such students
甩油罐的残液退至（）。
A、污油罐
B、重污油线
C、轻污油线
D、地沟
