code: function tag_sentence_wordnet(tagged_sentence, callback) {
    var wordnet_results = {};
    var nr_tokens = tagged_sentence.length;
  
    tagged_sentence.forEach(function(tagged_word) {
      logger.debug("tag_sentence: processing " + tagged_word);
      wordnet.lookup(tagged_word[0], function(results) {
        results.forEach(function(result) {
          if (tagged_word.lastIndexOf(result.pos) <= 0) {
            tagged_word.push(result.pos);
            logger.debug("Lexical category of " + tagged_word[0] + " is: " + result.pos);
          }
        });
  
        nr_tokens--;
        if (nr_tokens === 0) {
          logger.info("Exit tag_sentence_wordnet: " + JSON.stringify(tagged_sentence));
          callback(tagged_sentence);
        }
      });
    });
  }
docs: Tag the sentence using Wordnet Wordnet 'knows' only a limited set of lexical categories: n    NOUN v    VERB a    ADJECTIVE s    ADJECTIVE SATELLITE r    ADVERB If a word is not found in wordnet POS 'unknown' is assigned