their parents , wise folks that they are , read books 
(ROOT (S (NP (NP (PRP$ their) (NNS parents)) (, ,) (NP (NP (JJ wise) (NNS folks)) (SBAR (WHNP (WDT that)) (S (NP (PRP they)) (VP (VBP are))))) (, ,)) (VP (VBP read) (NP (NNS books)))))
(ROOT (S (NP (NP (PRP$ ) (NNS )) (, ) (NP (NP (JJ ) (NNS )) (SBAR (WHNP (WDT )) (S (NP (PRP )) (VP (VBP ))))) (, )) (VP (VBP ) (NP (NNS )))))