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问题 选择题

置换反应是化学反应的基本类型之一。金属与盐溶液之间的置换反应，一般是活动性较强的金属可把活动性较弱的金属从其盐溶液中置换出来。非金属单质也具有类似金属与盐溶液之间的置换反应规律，即活动性较强的非金属可把活动性较弱的非金属从其盐溶液中置换出来，如在溶液中可发生下列反应：

Cl2+2NaBr==2NaCl+Br2；Br2+2KI==2KBr+I2；I2+Na2S==2NaI+S↓

由此可判断下列化学方程式书写错误的是[ ]

A．Cl2+2NaI==2NaCl+I2

B．I2+2KBr==2KI+Br2

C．Br2+Na2S==2NaBr+S↓

D．Cl2+K2S==2KCl+S↓

答案

答案：B

单项选择题

生姜属于变态的（）。

A．根

B．茎

C．叶

D．果
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完形填空
下面是四位同学写给编辑Lee的求助信,请将这四封信与问题进行配对.
A
Dear Editor Lee,
I am a student from a junior middle school. I am good at all the subjects except English. I can’t remember words well. I am especially weak in speaking and listening. What shall I do? Could you give me some advice?
John
                              B
Dear Editor,
I have a problem! I really don’t know what to say when I meet strangers. I find it hard to talk with others because I’m afraid they might laugh at me. I am not as interesting, clever or funny as my friends. If people start talking to me, they will realize that I am just boring. Please help me.
Ann
                             C
Dear Editor Lee,
I was getting on well with my best friends. But a few days ago, another friend of mine told me that she often said bad words about me. When I heard this, I was very angry. What should I do? Should I stop being her friend or stay with her as usual?
Betty
                             D
Dear Editor Lee,
Recently I have much difficulty in falling asleep. When I go to bed, though I feel very sleepy, I always think a lot and can’t fall asleep. So I always feel very tired in class and sometimes my head hurts badly. Could you give me some advice?
Steven
小题1:The student finds it difficult to fall asleep.
小题2:The student doesn’t know what to say to strangers.
小题3:The student doesn’t know how to learn English well.
小题4:The student doesn’t know if she should still stay with her best friend.
小题5:请写出你的一个烦恼：________________________________________
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