Invited by Dr. Jean-Claude Chambron, Professor Leyong Wang visited Strabourg University from February 28 to March 4, 2019 and was invited to give a lecture. In Strasbourg, he met several famous scientists, especially Professor Jean-Pierre Sauvage and Professor Jean-Marie Lehn, and discussed with them. Strasbourg is a famous university city with a long history and unique culture. It is also the capital of Europe to a certain extent. Professor Leyong Wang also visited the old campus and the city center, and tasted local cuisine. Thank you Dr. Jean-Claude Chambron for his hospitality in Strasbourg.