多项选择题

B-D试验失败的常见原因是：（）

A.灭菌锅真空泵的效力下降，造成冷空气排出不完全
B.灭菌锅的机械故障造成真空泵的抽气时间缩短
C.灭菌锅的密闭性下降，不能维持有效的真空状态
D.灭菌锅的抽真空过程受影响，没有达到绝对的真空状态

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单项选择题

Sometimes I go to school（）car.

A、on
B、by
C、in

单项选择题

听力原文：W: Did you get the job you applied for?
M: No. It's been offered to someone else, but I think it wouldn't have suited me anyway.
Q: How does the man probably feel?
(2)
A．Worried.
B．Unhappy.
C．Pleasant.
D．It's OK.

A.
Q:
B.Worried.
B．Unhappy.
C．Pleasant.
D．It's
C.