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在过去的几年里，睡眠专家勒文·罗森费尔德（Leven Rosenfeld）在他的研究中发现，睡眠不足已成为一个全球性的问题，影响到了世界上的许多人。据罗森费尔德的研究，大约有三分之一的美国成年人每晚都无法获得足够的睡眠。他建议采取一些简单的步骤来帮助人们改善睡眠质量，例如限制咖啡因摄入，建立固定的睡眠时间，使用黑暗和安静的环境等。睡眠是人体恢复和再生的重要过程，我们需要认真对待。
In the past few years, sleep expert Leven Rosenfeld has found in his research that lack of sleep has become a global problem, affecting many people around the world. According to Rosenfeld's research, about one-third of American adults cannot get enough sleep every night. He suggests taking some simple steps to help improve sleep quality, such as limiting caffeine intake, establishing a regular sleep schedule, and using a dark and quiet environment. Sleep is an important process for the body to recover and regenerate, and we need to take it seriously. 

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