def words(num_of_word)
      target_len = num_of_word.times.inject(0){ |sum| sum + rand(@char_count_range_in_a_word) }
      sentence_key = bsearch(sentence_map_keys, target_len)
      unless sentence_key
        sentence_key = sentence_map.keys.min
      end
      wk_word = sentence_map[sentence_key].sample
      return wk_word.sub(/[#{ sentence_end_chars.join() }]$/, "")
    end
def words(num_of_word)
      target_len = num_of_word.times.inject(0){ |sum| sum + rand(@char_count_range_in_a_word) }
      sentence_key = bsearch(sentence_map_keys, target_len)
      unless sentence_key
        sentence_key = sentence_map.keys.min
      end
      wk_word = sentence_map[sentence_key].sample
      return wk_word.sub(/[#{ sentence_end_chars.join() }]$/, "")
    end
return rondom words from word resource

 @param [Fixnum] total count of word
 @return [String] words