
Chinese Ambassador to the United States Cui Tiankai addresses an event marking the 20th anniversary of Hong Kong's return to China in Washington D.C., capital of the United States, June 29, 2017. (Xinhua/Yin Bogu)

Chinese Ambassador to the United States Cui Tiankai addresses an event marking the 20th anniversary of Hong Kong's return to China in Washington D.C., capital of the United States, June 29, 2017. (Xinhua/Yin Bogu)