arena berlin chairs empty football grass large match nobody Olympic Games Olympic Stadium oval panorama racecourse soccer sport sports spring sunshine track and field athletics tribune view council cricket pitch flattened flattening green machine men at work pitch playing field preparation preparing reserve rolled roller rolling sporting sporting field work worker appropriate-behavior appropriate-behaviour black black and white canine communicating communication control controlled dog dogs hold-on informing lead leash outdoor-sport outdoors pets playing-fields public rules sign sporting-events sporting-field sporting-fields sports-oval under-control warning white active activities advice clothing coach coaches coaching football-field footballers grassed outdoor practice-match readiness ready sporting-area sports-green teenage Teenagers uniform uniforms young-people youth