    # File lib/active_support/core_ext/array/conversions.rb, line 10
            def to_sentence(options = {})
              options.assert_valid_keys(:connector, :skip_last_comma)
              options.reverse_merge! :connector => 'and', :skip_last_comma => false
              options[:connector] = "#{options[:connector]} " unless options[:connector].nil? || options[:connector].strip == ''

              case length
                when 0
                  ""
                when 1
                  self[0].to_s
                when 2
                  "#{self[0]} #{options[:connector]}#{self[1]}"
                else
                  "#{self[0...-1].join(', ')}#{options[:skip_last_comma] ? '' : ','} #{options[:connector]}#{self[-1]}"
              end
            end