According to China's dictionary, Yang Yuanhang is not an idiom, but a surname, or poplar. Set sail is a word, which means to raise the sail and start sailing. Sailing is to raise the sail. It means sailing or sailing. Set sail, that is, ships, planes, etc. Start sailing. From Liu Tang Changqing's poem "Send Judge Joe to Fuzhou": "Where to sail? Pinch the feathers and chase the east. There is no such idiom as John Young sailing.