code: def passage=(passage)
        sentences = passage.split(SENTENCE_DELIMITER).select { |sentence| sentence.chomp != '' }
        sentences.each { |sentence| self.sentence = sentence }
        add_weight :count, :sentence, sentences.count
      end
docs: Analyze passage
  
   Splits passage with sentence-ending punctuation, adds sentence count weight and analyzes each sentence
  
   @param [String] passage