must be the end of the world 
(ROOT (S (VP (MD must) (VP (VB be) (NP (NP (DT the) (NN end)) (PP (IN of) (NP (DT the) (NN world))))))))
(ROOT (S (VP (MD ) (VP (VB ) (NP (NP (DT ) (NN )) (PP (IN ) (NP (DT ) (NN ))))))))