!3 ''Change the length of a booking for the future'' |''begin transaction for client''| Joanna |''staff''| Bill| |''book''|2||coffee dispenser|''on''|2004/05/08 09:01|''for''|2 hours| |''pay with cash $''|6.00| |''complete transaction''| !3 ''One day later...'' |''time is now''| 2004/05/07 09:01| |''begin transaction for client''| Joanna |''staff''| Bill| |''change period of''|2||coffee dispenser|''for''|2004/05/08 09:01|''with duration of''|2 hours|''to''|5 hours| |''pay with cash $''|9.00| |''complete transaction''| * ''Checks'' |''client booking list''|Joanna| |''rental item''|''count''|''start date''|''end date''| |coffee dispenser|2|2004/05/08 09:01|2004/05/08 14:01| |''rental item subset''| |''name''|''free count''| |coffee dispenser|10|