People watch Giant Panda Bao Bao at the Smithsonian's National Zoo in Washington D.C., the Unite States, on Feb. 16, 2017. National Zoo holds a series of online and on-site events to bid farewell to Giant Panda Bao Bao from Feb. 16 to Feb. 20 before it departs for China on Feb. 21. (Xinhua/Yin Bogu)
