Professor Harro von Senger (R, Front), a famous Swiss Sinologist, communicates with Chinese culture fans during the exhibition "Charm of Chinese Culture: from Characters to Literature" at Palais des Nations in Geneva, Switzerland, on April 16, 2018. The exhibition was held here on Monday marking the Chinese Language Day, one of the days the United Nations sets aside for each of its six official languages. (Xinhua/Xu Jinquan)