节流器基本上（）油腔配置一个。
A.一个
B.一台设备
C.两个
D.三个
参考答案：A
—What’s your best friend like? —__________________
A．She is fine. Thank you.
B．She is a doctor.
C．She likes watching TV.
D．She is helpful and generous.
《水泥细度检验方法筛析法》规定试验筛使用（）次后，要进行清洗。
A.10
B.20
C.50
D.5
