如图，在密封的纸盒上挖一个直径10cm的圆形小洞，并在洞口前方约1米的位置，放置一根点燃的蜡烛，用双手在纸盒两侧拍击，蜡烛熄灭．蜡烛熄灭的主要原因是（ ）
A．缺乏可燃物
B．缺乏O2
C．排出的气流中CO2的含量高
D．温度降到了可燃物的着火点以下
A、蜡烛就是可燃物，故说法错误；
B、空气中有使蜡烛燃烧的充足的氧气，故说法错误；
C、纸盒中的气体也是空气，二氧化碳的含量与纸盒外的一样，故说法错误；
D、从纸盒小洞中喷出的气流使蜡烛的温度降到着火点一下，所以蜡烛熄灭，故说法正确．
故选D
 It is getting colder by the day. When I was putting out my autumn clothes, a brown woolen* sweater caught my eye and reminded of this time last year. It was on a cold morning that my mother came into my bedroom with the sweater. She said it was rather cold outside and asked me to wear it to school. “I spent the whole weaving* the sweater,” she told me. The sweater was so unfashionable and that I was not pleased with it. After mom went out to work, I the ugly sweater to a corner. I would rather catch a cold than wear it. I thought my classmates would laugh at me. I a thin uniform and went to school. Before I walked into the classroom, I heard Lana’s voice: “Look at my overcoat. My father bought it in Hong Kong.” Connie said: “My scarf is , too” I looked through the window and was surprised to see all the girls in colorful winter clothes me. They showed their clothes to each other and laughed . Suddenly, I felt inferior* to them. wasn’t my family as rich as theirs? I wanted to wear beautiful clothes, too. A strong cold wind blew and I sneezed. During class I felt terrible. The said I had caught a cold. “ You should wear thick clothes today, ” she said. I suddenly thought of my mom. She said the same thing to me I didn’t listen. As soon as I got home I fell asleep on the sofa. I of a woman weaving. She was my mother! She spent the whole night making a sweater for me. But I neither thanked her nor wore it. When I opened my _______, my mother was smiling at me. Her eyes were full of worry and care. I held her in my arms. “Sorry, mom, I should have complained about that sweater. ” Two days later, I wore the warm and comfortable woolen sweater to school. Some of my classmates laughed at me. But I didn’t . I know mom’s love is more important than money.
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