is like being trapped at a bad rock concert 
(ROOT (S (VP (VBZ is) (PP (IN like) (S (VP (VBG being) (VP (VBN trapped) (PP (IN at) (NP (DT a) (JJ bad) (NN rock) (NN concert))))))))))
(ROOT (S (VP (VBZ ) (PP (IN ) (S (VP (VBG ) (VP (VBN ) (PP (IN ) (NP (DT ) (JJ ) (NN ) (NN ))))))))))