我们已经知道，空气的主要成分是氧气和氮气，如下图所示是两套测

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问题实验题

我们已经知道，空气的主要成分是氧气和氮气，如下图所示是两套测定空气中氧气含量的实验装置图，请回答下列问题：

(1)请仔细观察比较甲、乙两套实验装置图。找出其中的不同，并说明设计的不合理性会给实验结果带来哪些问题（至少答出两点）。不同之处：____；影响结果____，不同之处：____；影响结果____

(2)这个实验除了可以得出氧气约占空气总体积的1/5的结论外，还可以推出氮气的物理____；氮气化学性质是____（填“活泼”或“不活泼”）

答案

(1)药匙的方向不同；甲会使测量结果偏低；导管伸入液面位置不同；甲会使测量结果偏低

(2)无色气体，不溶于水，也不与水反；不活泼

完形填空

Once upon a time, there was a little boy named Rakesh, he studied and lived in a boarding school(寄宿学校). Every night he jumped over the wall and played outside. He        returned before dawn (黎明) and lay on his bed again, so no one knew that Rakesh went out at        .
One night as usual, Rakesh found         asleep. He decided to play outside again. He went into his teacher—Mrs. Green’s room        and saw her        . Then Rakesh walked out towards the wall. Near the wall, there was a ladder in the bushes, he hid it there. He         the ladders and he climbed up it , then jumped over the wall.        at that time his teacher was awake and saw him going out.
      got up and took away the        from the wall. A few hours        , Rakesh returned. In the dark, he tried to climb        from the wall. Sadly, there was no ladder, instead, Mrs. Green was standing where the ladder was and waited for him. Rakesh was very        to be punished (处罚), but to his surprise, she just helped Rakesh to get onto the ground , said, "Rakesh, at least        a warm coat with you, when you go out at night."
Mrs. Green's        made Rakesh know his own faults. He apologized (道歉) and never went out at night again. It is the        lesson that he has ever had.

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写作题

近来我国多地雾霾天气不断增多，极大地影响了人们的健康与生活。请你根据提示，用英语写一篇文章，向某英语报社投稿。

提示：1. 实况描述

2. 对生活造成的影响

3. 分析雾霾形成的原因

4. 提出治理污染的建议。

注意：1. 上下文连贯，行文流畅。

2. 词数100-120 (首句已给出，并不计入词数)。

雾霾天气the hazy weather 口罩 mask

Dear Editor,

Recently many places in China were blanketed with thick fog.____________________________

Yours,

Li Hua

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