( ( ( ( Elements and ) Atoms ) ( An element ) ) ( ( is ( ( a ( pure substance ) ) ( that ( ( can not ) ( be ( decomposed ( by ( any ( chemical change ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NNPS Elements) (CC and) (NNPS Atoms)) (NP (DT An) (NN element))) (VP (VBZ is) (NP (NP (DT a) (JJ pure) (NN substance)) (SBAR (WHNP (WDT that)) (S (VP (MD can) (RB not) (VP (VB be) (VP (VBN decomposed) (PP (IN by) (NP (DT any) (NN chemical) (NN change)))))))))) (. .)))
Elements and Atoms An element is a pure substance that cannot be decomposed by any chemical change.
(ROOT (S (NP (PRP You)) (VP (VBP call) (NP (NP (DT a) (JJ pure) (NN substance)) (SBAR (WHNP (WDT that)) (S (VP (MD can) (RB not) (VP (VB be) (VP (VBN broken) (ADVP (RB down) (PP (IN into) (NP (NP (JJ different) (NNS types)) (PP (IN of) (NP (NNS substances)))))) (NP (DT a) (PRN (-LRB- -LRB-) (NP (NN n)) (-RRB- -RRB-)) (NN element))))))))) (. .)))