Technology has changed the nature of the billboard business, making it a more effective medium than in the past.
科技改变了广告牌行业的性质，使其成为比过去更有效的媒介。
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The car shaped some of the most lasting aspects of American culture: the roadside diner, the billboard, the motel, even the hamburger.
汽车塑造了美国文化中一些最恒久的一面：路边餐馆、广告牌、汽车旅馆，甚至汉堡包。
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"Dare to be different, please don't smoke!" pleads one billboard campaign aimed at reducing smoking among teenagers—teenagers, who desire nothing more than fitting in.