it 's like going to a house party and watching the host defend himself against a frothing ex-girlfriend . 
(ROOT (S (NP (PRP it)) (VP (VBZ 's) (PP (IN like) (S (VP (VP (VBG going) (PP (IN to) (NP (DT a) (NN house) (NN party)))) (CC and) (VP (VBG watching) (S (NP (DT the) (NN host)) (VP (VB defend) (NP (PRP himself)) (PP (IN against) (NP (DT a) (VBG frothing) (NN ex-girlfriend)))))))))) (. .)))
(ROOT (S (NP (PRP )) (VP (VBZ ) (PP (IN ) (S (VP (VP (VBG ) (PP (IN ) (NP (DT ) (NN ) (NN )))) (CC ) (VP (VBG ) (S (NP (DT ) (NN )) (VP (VB ) (NP (PRP )) (PP (IN ) (NP (DT ) (VBG ) (NN )))))))))) (. )))