He volunteered at the China Pavilion of the World Expo.
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culture
The 2010 Shanghai World Expo (上海世博会) was the largest in history with over 73 million visitors. Its mascot 海宝 and slogan 城市，让生活更美好 ('Better City, Better Life') are still recognized in China. Always written 世博会 in headlines, never the full 世界博览会.
