( ( The ( familiar ( chemical ( symbol ( H ( 2 O ) ) ) ) ) ) ( ( means ( that ( ( water molecules ) ( are ( composed ( of ( ( ( 2 ( hydrogen atoms ) ) and ) ( 1 ( oxygen atom ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (JJ familiar) (JJ chemical) (NN symbol) (NNP H) (CD 2) (NNP O)) (VP (VBZ means) (SBAR (IN that) (S (NP (NN water) (NNS molecules)) (VP (VBP are) (VP (VBN composed) (PP (IN of) (NP (NP (CD 2) (NN hydrogen) (NNS atoms)) (CC and) (NP (CD 1) (NN oxygen) (NN atom))))))))) (. .)))
The familiar chemical symbol H 2 O means that water molecules are composed of 2 hydrogen atoms and 1 oxygen atom.
(ROOT (S (NP (NP (CD 2) (NN hydrogen)) (, ,) (NP (CD 1) (NN oxygen) (NNS atoms))) (VP (VBP combine) (S (VP (TO to) (VP (VB make) (PRT (RP up)) (NP (NP (DT a) (NN molecule)) (PP (IN of) (NP (NN water)))))))) (. .)))
2 hydrogen, 1 oxygen atoms combine to make up a molecule of water.