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问题 选择题

如图所示的四种现象中，由于光的折射形成的是（　　）

A．

插入水中的铅笔好像折断了

B．

水中山的倒影

C．

屏幕上的手影

D．

瓶子在平面镜中的像

答案

A、水中铅笔变弯，是由于光的折射形成的；

B、倒影是由于光的反射形成的；

C、手影是由于光的直线传播造成的；

D、瓶子在平面镜中的像属于平面镜成像，是由于光的反射形成的．

故选A．

填空题

用have gone to / have been to / have been in / went to 填空。

1. _____ you ever _____ Disneyland?

2. How many times _____ you _____ Disneyland ?

3. I  _____ Nanjing since two years ago

4. Mr. Li  _____ Hong Kong. And he'll come back in two days.

5. —How long _____ you _____ Disneyland ?

    —For three days. I _____ the theme park last Sunday.

6. My father _____ Hong Kong two weeks ago.

7. My father _____ Hong Kong in 2005.

8. My father _____ Hong Kong since 2005.

9. My father _____ Hong Kong twice.

10. My father _____ Hong Kong and he hasn't come back yet.

11. —Where's Lucy?  

      —She has_____ to a restaurant for lunch.

12. Have you _____ to this park before.

13. I have_____ there only once this year.

14. She has _____ to the shop to buy a notebook.

15. You're late, Lao Wang has _____ to Guangzhou.
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单项选择题

全胃肠外营养支持患者可能发生的最严重的代谢并发症是（）

A.高钾血症

B.低钾血症

C.高血糖

D.高渗性非酮性昏迷

E.肝功能异常
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