in the worst elements of all of them 
(ROOT (PP (IN in) (NP (NP (DT the) (JJS worst) (NNS elements)) (PP (IN of) (NP (NP (DT all)) (PP (IN of) (NP (PRP them))))))))
(ROOT (PP (IN ) (NP (NP (DT ) (JJS ) (NNS )) (PP (IN ) (NP (NP (DT )) (PP (IN ) (NP (PRP ))))))))