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问题 选择题

下列器材或装置中，不是利用连通器原理进行工作的是　　　　　　　　　（　　）

A．喷水枪

B．船闸

C．锅炉水位计

D．茶壶

答案

答案：A

题目分析：喷水枪是利用水的压强的原理制成的，无论结构还是原理都不符合连通器；其它三个选项都使用了连通器。

故选A．

点评：记住连通器定义，生活中的锅炉水位计、自动喂水器、洗手盆的回水弯、过桥涵洞、船闸等等都是连通器．

选择题

中国新民主主义革命开始于[ ]

A、鸦片战争

B、辛亥革命

C、五四运动

D、新中国的成立
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单项选择题

When I was young, my parents ran a snack bar in our small town.One evening in early April, my mother told me to fill in at the snack bar (1) a worker who had the flu. I told her I would mess it up, (2) I had never worked at the bar before. I (3) that instead of making money, I would end up owing it."You can do it," said my mother," (4) , you won’t get much business until lunch. ""But I’ll never remember the orders, and I’m no good (5) money. Please, Mom, don’t (6) me."Then I’ll help you", she said.I shrugged my shoulders. I thought my mother’s (7) was a bad one, but I (8) .When I got to the bar the next day, I found my mother was (9) . Because the weather that day was rainy and cold, people wanted hot snacks and drinks. (10) , I was really slow at taking the orders and making change. The line of people grew, and everybody seemed (11) , I was so nervous that my hands shook, and I (12) a cup into pieces. What a mess! Then my mother came to (13) me, and she also showed me how to make (14) . If someone gave me $ 5 for something that cost $ 3.25, I handed over (15) quarters and a dollar and said, "75 cents makes four dollars, plus one dollar makes five. " Things went more (16) after that.By the end of the day, I could remember orders, (17) the bill, and make change quickly with a smile. I was even a little (18) when the sun came out and dried up business. My mother said she was proud of me, and when she (19) that I work at the snack bar again next year, I did not even shrug. I was too busy (20) the restaurant I would open one day.

 

第（17）空应选择（）

A．turn in

B．count out

C．take over

D．add up
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