it is hard to conceive anyone else in their roles . 
(ROOT (S (NP (NP (PRP it))) (VP (VBZ is) (ADJP (JJ hard)) (S (VP (TO to) (VP (VB conceive) (NP (NP (NN anyone)) (ADJP (JJ else))) (PP (IN in) (NP (PRP$ their) (NNS roles))))))) (. .)))
(ROOT (S (NP (NP (PRP ))) (VP (VBZ ) (ADJP (JJ )) (S (VP (TO ) (VP (VB ) (NP (NP (NN )) (ADJP (JJ ))) (PP (IN ) (NP (PRP$ ) (NNS ))))))) (. )))