题干

设数列{an},其前n项和Sn=﹣3n2,{bn}为单调递增的等比数列,b1b2b3=512,a1+b1=a3+b3.
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同类题1

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“读”出一个书香中国

李泓冰

    当网络横行全球,当微博华丽登场,阅读与写作的碎片化现象似乎已不可避免。不过,若是在这个盛夏光顾上海书展,看到那些酷暑中排长队购买入场券的读者,且大部分是年轻的面庞,不但关于纸质书末日的哀叹可以稍缓,也颇能体味一座城市的精神气质。

    这几天的上海,是最为全国读者、出版社、作家瞩目的地方。书展的成功,也向我们发出疑问:读书人的节日,能否可持续发展?阅读能否不仅仅是一年一度的盛大相约,更成为润物无声的日常习惯?

    比如,可否让传统的书店不那么急吼吼地退出历史舞台?尽管网上购书已成常态,但读者仍然需要阅读的氛围。在网络时代,如果还固守着当年新华书店的站柜卖书方式,书店的没落可想而知。而上海书展每天数十场作者与读者的互动、对话、签售,网上信息的充分发布,全场提供免费Wi-Fi,读者呼朋引类相约而来,既是阅读与购书的场所,也有了解作家、见识明星的机缘,还可以拿到小纪念品,或者只是一场以书为媒的社交、约会……正像上海书展的主题“我爱读书,我爱生活”-——读书,本来就该是生活的一部分。

    根据中国新闻出版研究院全国国民阅读调查课题组的研究,2011年我国公民人均阅读图书只有4.35本,上海领先全国,人均8本,而韩国人读11本、法国人20本、以色列人64本……

    重视教育的中国家庭,原来竟鲜有读书人么?除了教科书,我们的下一代真的没了阅读习惯么?

    试想,倘若官员忙于应酬惰于读书,我们只能坐视各处焚琴煮鹤、荼毒人文的事件层出不穷,更无法指望社会管理的规则意识;倘若学生深陷题海无暇读书,我们只能眼睁睁看着生机勃勃的孩子变成刻板僵化的应试机器,不但失掉创新的欲望与能力,更可能耽于本能冲动而拙于理性表达;倘若我们的社会弥漫着追逐物质、不屑读书的风气,更会与书籍带来的“高贵、力量、优雅和美”绝缘,挡住中国走向现代化的路途……“书犹药也,善读之可以医愚”。开卷与否,兹事体大!

    阅读习惯是需要培养的。如果有出了家门抬眼就能看到的社区图书馆,有在地铁站台相约时可以兜兜转转的人文书店,有班级里的图书角、学校里的阅览室,也有像年复一年的上海书展那样,成为这座城市读书人的节日,公众就有机缘体会对阅读的如饥似渴,体验思考的尊严,享受与智者对话的快乐。这也让我们温暖:未必是“大雅久不作”,公众并没有遗弃阅读,城市依然有可能成为爱书人的“书房”,很多现实疑团依然可能在阅读中丝丝缕缕地厘清……

    无书使人俗,没有书香的城市更会显得伧俗无礼。一场书展,透露了一座城市优雅的文化特征,也散发了令人欣慰的讯息:书事可为,阅读可期,民气可用,它作为公共服务的一种,在激励阅读、弥散书香方面,还有很多沉睡的领域有待开拓……

(选自《人民日报》,有删改)

同类题2

通读全文,根据短文理解,选择正确答案填空。   

    Once, in a small village, lived a family with eight children. Two of the children loved 1 very much, but the family was so poor that it was impossible to send 2 of them to study at the art college at the same time. After many discussions, the two boys finally 3 a plan. They would toss(抛) a coin. The loser would go 4into the mines (煤矿) and, with his earnings(赚得的钱), 5 his brother studying at the college. Then, when the brother who won the toss finished his studies, after four years, he would support the other brother studying at the 6.

    James won the toss and Jack went down into the mines. James worked with all his heart and his paintings were much 7 than those of most of his teachers, and by the time he 8, he was beginning to make a lot of money for his paintings.

    9 James returned, the family held a big dinner for his great success. Soon after the meal began, James 10 up from his seat to drink a toast (举杯祝酒) to his dear 11 He said, "Jack, now you can go to the art college and your 12 will come true. I will take care of you. "

    But Jack said 13, "Brother, the four years in the mines has done too much to my hands, so it's too 14 Now I can' t even hold a glass. "

    To show his great love and respect, James drew his brother' s hands with 15 towards the sky.

    He called his drawing "The Praying Hands", which became very famous years later.