Columbia University holds commencement ceremony

Graduates of School of International and Public Affairs (SIPA) wave flags during the commencement ceremony of the 264th Academic Year of Columbia University in New York, the United States, on May 16, 2018. Over 15,000 students graduate from the university this year. More than 35,000 students, guests, faculty and staff participated in the ceremony on Wednesday. (Xinhua/Michael Nagle)