( ( The ( ozone molecule ) ) ( ( contains ( ( three atoms ) ( -LRB- ( ( O 3 ) -RRB- ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN ozone) (NN molecule)) (VP (VBZ contains) (NP (NP (CD three) (NNS atoms)) (PRN (-LRB- -LRB-) (NP (NNP O) (CD 3)) (-RRB- -RRB-)))) (. .)))
The ozone molecule contains three atoms (O 3 ).
(ROOT (S (NP (NNP Water)) (VP (VBZ contains) (NP (CD 3) (NNS atoms))) (. .)))
Water contains 3 atoms.