In 1941, a large number of young American pilots, led by General Chennault, formed the American Volunteer Air Force to come to China to fight against the Japanese fascist invasion. The Chinese people affectionately called this force the "Flying Tigers". The "Flying Tigers" represent the responsibility of upholding justice and defending peace, and are engraved with the precious friendship of helping each other and sharing weal and woe. On September 25, local time, the "Flying Tigers Return Extra Close" graphic exhibition was held at California State Polytechnic University, Pomona, USA, exhibiting 140 hand-painted greeting cards created by primary and secondary school students from all over Yunnan Province, China. These greeting cards are full of friendship and blessings, bringing a special touch and surprise to the veterans of the Flying Tigers and their descendants.