dead end lines no pole post posts power sign signpost signposts signs sky steel stp sundtraffic traffic warning way yellow color correct error exclamation graphic green hand handwriting incorrect mistake opposite quiz red right text word written wrong yes mark black black on white direction law no alternative one way one way signs only specific street signs white blue left not prohibition road stop turn go human man walk walking lorry truck vehicle computer monitor different humorous keyboard Letterbox letterbox slot mail mail in monitor no email postage snail-mail unusual weathered acceptable access-denied access-limited advice advising alert allocated allocation approved authorised authorized automobiles behave carpark cars communicate communication denied directions directive entry-denied entry-prohibited information informing limited limited-parking motor-cars no-access no-entry not-allowed not-permitted parking permission-denied prohibited restricted restriction restrictions safety special-parking unauthorised unauthorized vehicles vistors