VOA慢速英语：国际大事成今年美国高校毕业演讲主题
来自：VOA英语网 文章地址: http://livechatworks.com/18/05/Graduation-Speeches-Discuss-World-Problems-Look-for-Solution.html
来自：VOA英语网 文章地址: http://livechatworks.com/18/05/Graduation-Speeches-Discuss-World-Problems-Look-for-Solution.html