Flying like a duck
Explanation: Going fast: walking fast; duck: a wild duck. Running in a flock like ducks. It is a metaphor for a group of people chasing after something improper, and it has a derogatory connotation.
Origin: Ru Xun can also write poems, scholars flock to him like ducks, and the seats are always full. ---------"History of the Ming Dynasty·The Biography of Xiao Ruxun"
Crossing the River
Note: The detailed explanation of this idiom is: When the Western Jin Dynasty fell, the Central Plains was in chaos, and famous people in the Central Plains They came to Jiangnan one after another. Hence the poem "There are more famous people crossing the river than crucian carp". Later it was used to describe many people who follow the trend.