奥巴马何时卸任？

中文段落：

奥巴马，全名巴拉克·侯赛因·奥巴马，是美国历史上第一位非洲裔总统。他的任期开始于2009年1月20日，并在2017年1月20日结束，因此奥巴马卸任的时间是2017年1月20日。

奥巴马在任期内推动了许多重要的政策和改革，包括美国经济复苏计划、医疗保险改革、金融监管改革、能源和气候变化政策等。他还积极倡导国际合作，致力于解决全球性问题，如反恐、气候变化和全球经济发展等。

奥巴马的卸任标志着美国政治舞台上的一次重要转变。他的继任者特朗普在政策方向和外交策略上与奥巴马有很大不同，这给美国乃至全球的政治和经济格局带来了新的挑战和机遇。

总的来说，奥巴马在任期内取得了许多成就，他的领导风格和政策理念对美国和全球产生了深远的影响。尽管他的卸任标志着一个时代的结束，但他的贡献和影响将永载史册。

英文段落：

Barack Hussein Obama, commonly referred to as Obama, was the first African-American president in the history of the United States. His presidency began on January 20th, 2009, and concluded on January 20th, 2017, marking the date of his departure from office.

During his presidency, Obama pushed forward numerous significant policies and reforms, including the American Recovery and Reinvestment Act, healthcare reform, financial regulatory reform, and energy and climate change policies. He also advocated for international cooperation and addressed global issues such as counter-terrorism, climate change, and global economic development.

Obama's departure marked a significant transition in American politics. His successor, Donald Trump, differed significantly from Obama in terms of policy directions and foreign strategies, posing new challenges and opportunities for the political and economic landscape of the United States and the world.

Overall, Obama achieved numerous accomplishments during his presidency, and his leadership style and policy philosophy had a profound impact on the United States and the global community. While his departure signaled the end of an era, his contributions and influence will forever be recorded in history.