clean clean up compulsory green litter man mandatory Mandatory sign no litter no trash no waste roadsign roadsigns sign signs trash trash can UP waste arrow down forward left plate right road srtraight street traffic transport way cannon circle conflict enemy peace politics prohibitory red tank war warning wars chinese clever knowledge letter nonsence rule rules stop stopped strange ting understand understandable auto bus buses busses car minibus post pylon transportation travel chains heavy snow iced icy mountains safe snow snow chains snow chains compulsory wheel wheels winter allowed banned banner canine dog dogs lace lead leash leashed dog line lined not allowed unleash unleashed dog animal illegal no dog no dogs poop prohibit prohibition shit walking