Sentence:  The three traditionally recognized Non-modal <WSD>Auxiliaries</WSD> are the per-/ fective <WSD>Auxiliary</WSD> "have", the progressive <WSD>Auxiliary</WSD> "be", and the passive <WSD>Auxiliary</WSD>/ "be". Perfective "have" is so-called because it marks the completion (hence, "perfec-/ tion") of an action; it is followed by a VP headed by a perfective "-n" participle, as/ in:/ (121)    The referee has [<sub>VP</sub> "shown" him the red card] 
Meaning of the word marked with <WSD> tags:  An auxiliary verb.