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问题 单项选择题

以下（）信号不能作为信息的载体使用。

A．电信号

B．磁信号

C．光信号

D．飞信号

答案

参考答案：D

解析：

信号是信息的载体。常用的信号表现形式有电、磁、机械以及热、光、声等。

[点评] 本题考察的知识点是信号作为信息的载体常用的表现形式。

填空题

用come短语的适当形式填空。

1. The school has very good teachers, but when it ____ buildings, the school is poor.

2. The teacher asked a difficult question, but finally a boy student ____ a good answer.

3. He is not rich; his earnings ____ only $6,000 a year.

4. My grandpa was so lucky to ____ the operation on his heart.

5. My uncle promised to ____ and fetch me.

6. Christmas will soon ____.

7. That magazine ____ once a week.

8. How did the movie finally ____? I couldn't wait to see the ending.

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单项选择题

起于内斜线的是（）

A.下颌舌骨肌

B.茎突舌骨肌

C.颊肌

D.斜角肌

E.上唇方肌
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