border descent exclamation red road sign steep triangle warn warning white advice alert appropriate-behavior appropriate-behaviour avoid black bright care concern denied directions limitations limited limited-entry not-allowed not-permitted permission-denied prohibited prohibition restricted restrictions rules signs vehicles warning sign yellow attention danger deer germany isolated pictogram safety traffic ban banned call cell cellphone dial digital illegal mobile no phone prohibit proscription roadsign tall access-denied communicating communication exceptions regulations responsible warning-sign announcement be-careful beware careful caution dangerous informing Look looking lookout observant risk risks watch watch-out commute commuter public transport shuttle tram tramway tramways blue clouds san diego sky stop sign words