today expo is the economic and cultural olympiad of the world, 第一范～文网ｗｗｗ. DiYiFаn Wen.com整理该文章，版权归原作者、原出处所有。a competition among nations, as well as among exhibitors from the private sector on a given subject. at the same time, it is about marketing countries internationally. expositions of the first category last a maximum of 6 months and may be held on an enormous..