How do I get my output to be like Jason's?

class Address
  attr_accessor :kind, :street_1, :street_2, :city, :state, :postal_code

  def to_s(format = "short")
    address = " "
    case format
    when "long"
      address += street_1 + "\n"
      address += street_2 + "\n" if !street_2.nil?
      address += "#{city}, #{state} #{postal_code}"
    when "short"
      address += "#{kind}: "
      address += street_1
      if street_2
        address += " " + street_2
      end
      address += ", #{city}, #{state}, #{postal_code}"
    end
    address
  end
end

class PhoneNumber
  attr_accessor :kind, :number

  def to_s
    "#{kind}: #{number}"
  end
end

require "./phone_number"
require "./address"

class Contact
  attr_writer :forename, :middle_name, :surname
  attr_reader :phone_numbers, :addresses

  def initialize
    @phone_numbers = []
    @addresses = []
  end

  def add_phone_number(kind, number)
    phone_number = PhoneNumber.new
    phone_number.kind = kind
    phone_number.number = number
    phone_numbers.push(phone_number)
  end

  def add_address(kind, street_1, street_2, city, state, postal_code)
    address = Address.new
    address.kind = kind
    address.street_1 = street_1
    address.street_2 = street_2
    address.city = city
    address.state = state
    address.postal_code = postal_code
    addresses.push(address)
  end  

  def forename
    @forename
  end

  def middle_name
    @middle_name
  end

  def surname
    @surname
  end

  def forename_first
    forename + " " + surname
  end

  def surname_first
    surname_first = surname
    surname_first += ", "
    surname_first += forename
    if !middle_name.nil?
      surname_first += " "
      surname_first += middle_name.slice(0, 1)
      surname_first += "."
    end
    surname_first
  end

  def full_name
    full_name = forename
    if !middle_name.nil?
      full_name += " "
      full_name += middle_name
    end
    full_name += ' '
    full_name += surname
    full_name
  end

  def to_s(format = "full_name")
    case format
    when "full_name"
      full_name
    when "surname_first"
      surname_first
    when "first"
      forename
    when "last"
      surname
    else
      surname_first
    end
  end

  def print_phone_numbers
    puts "Phone Numbers"
    phone_numbers.each { |phone_number| puts phone_number }
  end

  def print_addresses
    puts "Addresses"
    addresses.each { |address| puts address.to_s("short") }
  end
end

sean = Contact.new
sean.forename = "Sean"
sean.middle_name = "Michael"
sean.surname = "Flanagan"
sean.add_phone_number("Home", "123-456-7890")
sean.add_phone_number("Work", "456-789-0123")
sean.add_address("Home", "123 Main St.", "", "Portland", "OR", "12345")

puts sean.to_s("full_name")
sean.print_phone_numbers
sean.print_addresses

require "./contact"

class AddressBook
  attr_reader :contacts

  def initialize
    @contacts = []
  end

  def print_contact_list
    puts "Contact List"
    contacts.each do |contact|
      puts contact.to_s("surname_first")
    end
  end
end

address_book = AddressBook.new

sean = Contact.new
sean.forename = "Sean"
sean.surname = "Flanagan"
sean.add_phone_number("Home", "123-456-7890")
sean.add_phone_number("Work", "456-789-0123")
sean.add_address("Home", "123 Main St.", "", "Portland", "OR", "12345")

marcia = Contact.new
marcia.forename = "Marcia"
marcia.surname = "Scott"
marcia.add_phone_number("Home", "222-222-2222")
marcia.add_address("Home", "222 Two Lane", "", "Portland", "OR", "12345")

address_book.contacts.push(sean)
address_book.contacts.push(marcia)

address_book.print_contact_list