What do you mean, you often walk by the river and don't wet your shoes?

"How can you walk by the river often without getting your shoes wet?" That is to say, if you walk by the river often, your shoes will inevitably get muddy and water. This sentence is usually used to mean that people who have been in bad environment or engaged in dangerous work for a long time will inevitably be affected by bad environment or make mistakes. This sentence emphasizes the influence of environment on people, but it also reminds people that although the external environment may have an impact on people's behavior, internal principles and firm will are the key to resist these influences. Therefore, this sentence is also encouraging people to maintain their own principles and ethics, even in a difficult environment, and strive to remain innocent.