code: private boolean inStartSet(String tag) {
          return
              // noun
              tag.startsWith("NN") ||
              // adjective
              tag.startsWith("JJ") ||
              // adverb
              tag.startsWith("RB") ||
              // cardinal number
              tag.startsWith("CD");
      }
docs: Checks to see if the tag can modify another word
  
  @param tag A tag from the parsed corpus to be checked