120阀中（）的作用是控制列车制动时列车管第二阶段局部减压量。_爱下问搜题

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问题单项选择题

120阀中（）的作用是控制列车制动时列车管第二阶段局部减压量。

A.加速缓解阀

B.主阀

C.局减阀

D.紧急二段阀

答案

参考答案：C

单项选择题

弦脉的脉象主要表现为（）。

A．脉位的变化

B．脉宽的变化

C．脉力的变化

D．紧张度的变化

E．节律的变化

补全对话，情景问答

从方框中选择合适的句子补全对话。

A. And what about you?
B. Lucy is speaking English.
C. This is Lucy speaking.
D. What's Dad doing?
E. And how about the weather in New York now?
F. Is Dad cooking?
G. She's watching TV and eating hamburgers.

A: Hello. This is Jeff  from Boston.
B: Hi, Jeff      1      How's it going?
A: Pretty  good.
B: How's the weather in Boston?    .
A: It's raining.      2   _
B: It's sunny.
A: Great !     3
B: He's cooking hot dogs.
A: Is Mom cooking, too?
B: No.     4      .
A:      5
B: I'm eating an apple and talking to you.