tokens: This includes ReVerb , a shallow extractor that addresses three common errors of hitherto existing Open IE systems : the output of such systems frequently contains a great many of uninformative extractions ( i.e. extractions that omit critical information ) , incoherent extractions ( i.e. extractions where the relational phrase has no meaningful interpretation ) and overly - specific relations that convey too much information to be useful in further downstream semantic tasks .