2) Warning signs are graphic signs used to remind people to pay attention to their surroundings to avoid danger. The basic form is a black regular triangle border, the figure is black, and the background is yellow.

3) The instruction sign is the basic form of the graphic sign used to force people to make a certain action or have to take certain precautions.

4) The prompt flag is a graphic flag used to provide people with all the position and direction information of the target. The basic form is a rectangular border, the graphic text is white, and the background is the provided logo, which is green. Fire equipment reminder sign with red.

Language is a tool for human beings to convey thoughts and feelings. Warning signs are one of the standards for improving and measuring the maturity of urban construction and development, ensuring people's safety, and playing a positive publicity effect for urban civilization construction.