一辆小汽车每小时行54千米， $\frac{5}{6}$ 小时行____千米．

请你根据同学们找到的三则材料，简要概括公共图书馆讲座的四个特点。
【材料一】
南京图书馆举办的“明孝陵遗址公园”、“大报恩寺的前世今生”等讲座, 突出本地特色, 加深了听众对地方文化的了解。明故宫资深研究专家开设的“走进故宫”大型系列讲座，推出了“光凝秋水寒”、“盛世琢华琼”、“紫气贯京华”等专场，给广大“明故宫迷”提供了一个系统了解明故宫的平台。
【材料二】
南京图书馆开设的“市级领导干部讲座”，主要针对市级领导干部的需求，突出执政能力建设的主题。在新年到来之际，针对南京图书馆少年儿童馆“新年阅读计划”的启动活动，著名儿童文学家杨红樱开设了题为“马小跳的童年意义”的讲座，为少年儿童听众送上了一份特殊的新年礼物。
【材料三】
上海图书馆讲座紧贴时代脉搏，在上海两会召开前夕，开设大型时政讲座“转型•创新•发展”，倾力推出“转型中的社会治理”、“以文化方式创新”、“上海转型的进行时与将来时”等系列讲座。由古城卫士阮仪三先生主讲的“从石库门看上海建筑的百年文脉”，让人们了解了代表城市文化记忆的石库门在旧城新建中的价值，强调了保护地域特色古建筑的重要性。
特点：
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阅读理解

    Last year my summer holiday was spoiled by my bringing along a modern convenience that was too convenient for my own good: the iPad. Instead of looking at nature, I checked my e-mail. Instead of paddling a small boat, I followed my Twitter feed（推特简讯）. Instead of reading great novels, I stuck to reading four newspapers each morning. I was behaving as if I were still in the office. My body was on vacation, but my head wasn't.

    So this year I made up my mind to try something different: withdrawal from the Internet. I knew it wouldn't be easy, since I'm bad at self-control. But I was determined. I started by giving the iPad to my wife.

    The cellphone signal at our house was worse than in the past, making my at tempts at cheating an experience in frustration （沮丧）. I was trapped, forced to go through with my plan. Largely breaking away from e-mail, Twitter and my favorite newspaper websites, I had few ways to connect to the world except for the radio—and how much radio can one listen to, really? I had to do what Ihad planned to do all along: read books.

    This experience has had a happy ending. With determination and the strong support of my wife, I won in my vacation struggle against the Internet, realizing finally that it was I, not the iPad, that was the problem. I knew I had won when we passed a Star bucks and my wife asked if I wanted to stop to use the Wi-Fi.“I don't need it,” I said．

    However, as we return to post-vacation life, a harder test begins: Can I continue when I'mback at work?

    There are times when the need to know what's being said right now is great. I have no intention of giving up my convenience completely. But I hope to resist the temptation to check my e-mail every five minutes, which leads to checking my Twitter feed and a website or two.

    I think a vacation is supposed to help you rest your brain to become more productive. Here I hope this one worked.