( elements substances )
(ROOT (NP (JJ elements) (NNS substances)))
elements substances
(ROOT (S (NP (NP (NNS Substances)) (SBAR (WHNP (WDT that)) (S (VP (MD can) (RB not) (VP (VB be) (VP (VBN broken) (PRT (RP down)) (PP (IN into) (NP (NP (JJR simpler) (NNS substances)) (PP (IN with) (NP (JJ different) (NNS properties))))))))))) (VP (VBP are) (VP (VBN called) (NP (NNS elements)))) (. .)))