题干

光敏电阻的特点是有光照射它时阻值变小.如图所示是某小区门口利用光敏电阻设计的行人监控装置,R1为光敏电阻,R2为滑动变阻器,A,B间接监控装置.则(   )

A:当有人通过通道而遮蔽光线时,A,B间电压降低

B:当有人通过通道而遮蔽光线时,A,B间电压升高

C:当仅增大R2连入电路中的阻值时,通过R1的电流变大

D:当仅增大R2连入电路中的阻值时,可降低A,B间的电压

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A

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单词拼写

    Paper cutting is a traditional art in China. It has been around for____(多于)1,500 years. This kind of art went after the invention of p____in Han Dynasty.

    It once became one of the main____fᴐ:(r)mz of art, and____(受…欢迎) the people of that time; e____in royal (王室的) families, ladies were also judged by the ability at paper cutting.

    Most of the papercut artists are w____. The themes of their works usually include everything in people's____(日常生活),such as flowers, animals, and things about Chinese history. Familiarity (熟悉) makes them understand the real spirit of the art.

    The main tool for paper cutting is s____ Once they are owned by a master of papercut, they will become so supernatural (超自然的)____the papercuts beyond imagination flow out (倾泻) of his/her hands. Another tool____paper cutting is carving knives which are necessary to improve a sharpened effect or to make a good job. It's believed that art____(来自) life and serves life. The bright colors of red, green or light blue papercuts provide a merry atmosphere.____they are often found in wedding ceremonies or festivals in China. And people like to decorate____windows and doors u____colorful papercuts.

    Papercuts made____(在不同地区) have different characteristics. Shanxi window papercuts are simple and bold (轮廓突出的) ; papercuts from Hebei Province are bright in color; papercuts in southern provinces are good and fine.