having an old friend for dinner ' 
(ROOT (S (VP (VBG having) (NP (DT an) (JJ old) (NN friend)) (PP (IN for) (NP (NN dinner)))) ('' ')))
(ROOT (S (VP (VBG ) (NP (DT ) (JJ ) (NN )) (PP (IN ) (NP (NN )))) ('' )))