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问题 选择题

保持二氧化碳的化学性质的最小微粒是

A．CO2

B．O2

C．C

D．2O

答案

答案：A

能直接构成物质的粒子有三种：分子、原子、离子，物质是由什么粒子直接构成的，它的化学性质就是由谁来保持的，二氧化碳是由二氧化碳分子构成的，所以保持二氧化碳化学性质的粒子是二氧化碳分子．

故选A

单项选择题

患者男性，23岁。两周前因足球赛中出现摔伤导致右腿胫骨骨折而行手术。

现病人宜采取的体位是

A．平卧位

B．中凹卧位

C．头低足高位

D．头高足低位

E．侧卧位
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填空题

用所给词的正确形式填空 。

1. How long              he              (read) English every night?

2. I have some              (knife). I can lend one to you.

3. My brother often goes to school without              (eat) breakfast.

4. Before, Kitty seldom               (have) fruit and vegetables.

5. Would you like               (buy) fish？

6. I play computer games              (two) a week.

7. My teacher says it is very important              (sleep) well before an exam (考试).

8. Those              need a lot of time              every day. (dance)

9. The fish is too              (salt). I don't want to eat it.

10. Daniel usually              (have) meat and vegetables for dinner now.

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