If you are using a crosswalk to cross the street, you should look carefully to the left, right and left again to be sure it is safe to cross. This sign means that you are coming to an intersection and should be prepared to stop. At a busy intersection, it is safer to walk your bike across the street instead of riding it. This sign means you are near a school crossing zone. This sign means you are coming to a railroad crossing.
Railroad tracks are uneven.
You should not try to bicycle or in-line skate over them. When people are working on the roads, parts of the road or sidewalk are often dug up or rough. Be careful when walking, bicycling or in-line skating. Uneven, rough roads could make you fall off your bike or in-line skates. If you must move into the road to go around a work area, you should stop and look carefully to be sure there is no traffic coming before going into the road.