A student performs an exercise during a class of the level 4 of the Chinese language, in a classroom of the Universitary Languages Centre sponsored by the Confucius Institute of Buenos Aires, in Buenos Aires city, capital of Argentina, on Sept 26, 2014. The Day of the Confucius Institute is celebrated worldwide on Sept 27, marking the 10th anniversary of the stablishment of the Confucius Institute. [Photo/Xinhua]