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问题 单项选择题

锁相环路的基本组成包括（）。

A.鉴相器（PD)、低通滤波器（LPF)、压控振荡器（VCO）

B.PD和VCO

C.PD和LPF

D.PD、LPF、VCO、HPF

答案

参考答案：A

阅读理解

读短文，将正确答案的序号填入题前括号里。

      Hello, I'm Peter. I'm a student. Usually I go to school on foot. Because my home is near the school. My

father is a teacher. He often goes to work by subway. Sometimes he goes to work by taxi. My mother is a

nurse. She usually goes to work by bus. Sometimes she goes to work by bike.

1. Usually Peter goes to school ______________. 

A. by bus

B. on foot

C. by car

2. Peter's father is a ______________. 

A. teacher

B. driver

C. doctor

3. Sometimes Peter's father goes to work ______________. 

A. on foot

B. by taxi

C. by subway

4. Peter's mother is a ______________. 

A. farmer

B. nurse

C. baseball player

5. Peter's mother always goes to work ______________. 

A. by bus

B. by bike

C. by car
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单项选择题 A3/A4型题

患者，男性，26岁，舌部溃疡1个月。患者近2月来，低热、乏力、盗汗。体检：舌部右侧溃疡，较深，约1cm×0.5cm，边缘不齐，表面假膜，基底有细小的颗粒状结节，触痛明显。

为尽早做出诊断，首选的检查方法为（）

A.血培养

B.胸透或胸片

C.标本动物接种

D.结核菌素试验

E.活检
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