1.Dear Alice，
    You really have two different questions here，so we'll discuss them one at a time．
    Your problems at school may be a result of a number of things．You don't say much about how these classmates get along with each other．It's possible that all the students are feeling a little cautious(谨慎的) in the first term．
    It's also possible that the others are unkind．If this is so，you have to find out why you are the class “outsider．”
In your letter you say you often offer to help others with their work．Is it possible that your classmates don't understand your offers? Could it seem that you were trying to“buy”friends with these offers?
    Is it possible that you took no notice of your classmates when you had your good friend near you? They may have felt hurt at that time．It may take a time for them to believe in you if so．Try to ask one classmate directly what the problem is．If you hear a negative(负面的)answer，at least you'll know what to do．
Yours truly，
Shelia

2.小明同学将一块光亮的纯铜片放在酒精灯火焰上灼烧，发现铜片表面全部变黑．请你一起参与以下探究．
(1)提出问题：黑色物质的成分是什么? (2)查阅资料：①酒精在不完全燃烧时会产生炭黑．
②炭黑不与稀酸反应，也不溶于稀酸；氧化铜可与稀酸反应而溶解．
(3)猜想与假设：黑色物质可能是a：氧化铜，b：炭黑，c：{#blank#}1{#/blank#}    
(4)实验方案：取一小片变黑的铜片，放入盛有足量{#blank#}2{#/blank#} (填化学式)溶液的试管中，观察现象．
(5)现象与结论：若现象是{#blank#}3{#/blank#} ， 则猜想a正确，试写出发生反应的化学方程式{#blank#}4{#/blank#}；

3.

    “Who did this?” asked my teacher. Thirty children tried to think about not only what they had done, but also what our teacher might have found out.
    “Who did this?” she asked again. She never became angry, but she was this time. She held up a piece of broken glass and asked, “Who broke this window?”
    “Oh, oh,” I thought. I was the one who broke the window. I did not do it on purpose (故意). It was caused by a bad throw of a baseball. Why did it have to be me?
    If I admitted (承认) it, I would be in a lot of trouble. How would I be able to pay for a big window like that? “My father is going to get angry at me,” I thought. I didn't want to raise (举起) my hand, but something much stronger than me pulled it up. “I did it,” I said. Then I was silent. It was hard enough saying what I had.
    My teacher went to one of our bookshelves and took down a book. She then began walking towards my desk. I had never known my teacher to strike (打) a student, but I feared she was going to start with me.
    “I know how you like birds,” she said as she stood looking down at my face. “Here is the field guide about birds (鸟类野外指南) that you always check out from our school library. It is yours now. We have got a new one for the school. You will not be punished (惩罚). But remember, it's only for your honesty.”
    I couldn't believe it! I wasn't being punished and I was getting my own bird field guide, the one that I had been saving up all my money to buy.

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