Does the slogan prohibiting fishing serve as a guide or as a function?

The slogan prohibiting fishing serves as a guide. No fishing signs clearly tell people that fishing is prohibited and will be posted in public places or specific areas to remind people not to engage in fishing activities. Through these signs, people can have a clearer understanding of local regulations and laws and avoid fines or other penalties for violating relevant regulations. Therefore, the slogan prohibiting fishing serves as a guide.