题干

以下是某化学反应的微观示意图( 分别表示不同元素的原子),下列对图示反应的理解中,正确的是                  (         )

A:反应物和生成物中共含有三种元素

B:参加反应的物质分子个数之比为1:1

C:反应物和生成物中只有一种物质

D:该反应属于化合反应

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答案(点此获取答案解析)

D

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    When I was a junior high school student in 1980, God gave me a gift, it was happiness.

    One weekend, I went to visit my grandparents in the countryside. On my way home a car ran over me and cut off my1because of its high speed.

    Several days later when I woke up at the hospital, I realized I had to spend the rest of my life2arms. How sad I felt at that time! Even I was full of fears.3slowly I knew I had to face the fact and got over it. I couldn't get my arms back even though I4every day.

    However, it's easier to5than to do. It6me nearly half a year to get out of the sadness completely. I got so much from my7story. From then on, I could treat my life with a normal(正常的) mind. But in our daily life, I often see my classmates get8about little things: They get a bad grade on a test; their bus comes9; they don't have a mobile phone but10have, and so on. But I only11life. I was lucky to realize from an accident: It is a waste of our life to focus on(关注)what you have12. We should always think of what we have. So why are so many people unhappy? Someone may say, “My whole life would improve13I have a new car.” But when you get the car and what14? For a whole week you are walking on air. Then you go right back to being unhappy.

    Happiness depends on(取决于) what we have! It's in our heart. It's a state of mind, even though you own the whole world, you may still feel15.Happiness comes from mastering the art of appreciating(感激) and taking pleasure in what you really have.