A Letter to the department Dear Sir or Madam, I'm writing to express my disappointment. The unpleasant memory for seeing an aged man walking anxiously along the street and looking in vain for a taxi is still vivid.Generally speaking, unavailability of the aged for taxi service is unexpected and annoying.Taxi drivers mostly use the taxi-booking software to improve the efficiency of their services.Most frequently,taxies running along the street have been ordered through the taxi-booking software.I'm sad that there rarely are empty taxies available to the aged. Ignorance of aged people's inability to use the modern software is to blame for the embarrassing situation.I hope an effective solution could be achieved. You are expected to arrange telephone booking service or reserve more empty taxies for aged people. Sincerely, XXX