2. The colors are white background, red circle, red stripe, black pattern and patterned layering: no sign.
3. The color is blue background and the white pattern is indicator.
4. Expressway with blue background, white pattern and green background, with white pattern: guide sign.
5. Orange or fluorescent orange: warning and guiding signs in road operation areas.
6. Fluorescent yellow-green: a warning sign for pedestrians and children.
Extended data:
The shapes of traffic signs represent the following signs:
1. equilateral triangle: used as warning sign.
2. Circle: used to prohibit and indicate signs.
3. Inverted equilateral triangle: a forbidden sign for "slowing down and giving way".
4. Octagonal: a prohibition sign for "stopping and giving way".
5. Fork: Used as a warning sign of "Railway Crossing Fork Sign".
6. Square: used for guiding signs, some warning, prohibition and indication signs, tourist area signs, auxiliary signs and notification signs.
References:
Baidu encyclopedia-traffic signs