Finally, to demonstrate the value of such a highly pure list of closed-class words, which previously could not be acquired through unsupervised learning, we plug the acquired list into a previously existing minimally supervised tagging system, (Zhao  Marcus, 2009), which only requires a closedclass lexicon for tagging all words.
after running the bootstrapping algorithm for words, we have already obtained a list of words that can be used for filtering the output of the baseline models.