animals prohibited appropriate behavior appropriate behaviour bicycles prohibited black black and white communicating communication denial denied dog informing littering prohibited no animals no bicycles no littering not allowed not permitted permission denied prohibited prohibition prohibitions rules sign warning white allow allowed bicycle bicycles bike bikes post roadsign roadsigns signs access-denied access-limited advice alert announcement appropriate-behavior appropriate-behaviour ban banned be-careful beware bicycles-prohibited bylaws concern danger dangerous directions information law legal no-wheels not-allowed not-permitted parking pedestrian-care pedestrian-safety permission-denied restricted restriction restrictions risk risks rollerskates-prohibited safety skateboards-prohibited warning-sign watch watch-out cycling-prohibited no-bikes no-cycling symbol