that should be punishable by chainsaw 
(ROOT (S (NP (DT that)) (VP (MD should) (VP (VB be) (VP (VBN punishable) (PP (IN by) (NP (NN chainsaw))))))))
(ROOT (S (NP (DT )) (VP (MD ) (VP (VB ) (VP (VBN ) (PP (IN ) (NP (NN ))))))))