( DNA ( ( consists ( of ( ( two ( 1 ( 20 ( long chains ) ) ) ) ( of ( nucleotides ( twisted ( into ( ( ( a ( double helix ) ) and ) ( ( 1 21 ) ( joined ( by ( ( hydrogen bonds ) ( between ( ( the ( complementary bases ) ) ( ( 1 22 ) ( ( adenine and ) ( thymine ( or ( ( cytosine and ) guanine ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP DNA)) (VP (VBZ consists) (PP (IN of) (NP (NP (CD two) (CD 1) (CD 20) (JJ long) (NNS chains)) (PP (IN of) (NP (NP (NNS nucleotides)) (VP (VBN twisted) (PP (IN into) (NP (NP (DT a) (JJ double) (NN helix)) (CC and) (NP (NP (QP (CD 1) (CD 21))) (VP (VBN joined) (PP (IN by) (NP (NP (NN hydrogen) (NNS bonds)) (PP (IN between) (NP (NP (DT the) (JJ complementary) (NNS bases)) (ADJP (NP (QP (CD 1) (CD 22))) (ADJP (ADJP (JJ adenine)) (CC and) (ADJP (JJ thymine) (CC or) (JJ cytosine) (CC and) (JJ guanine)))))))))))))))))) (. .)))
DNA consists of two 1 20 long chains of nucleotides twisted into a double helix and 1 21 joined by hydrogen bonds between the complementary bases 1 22 adenine and thymine or cytosine and guanine.
(ROOT (S (NP (DT The) (JJ double) (NN helix) (NN dna) (NN shape)) (VP (VBZ forms) (SBAR (WHADVP (WRB when)) (S (NP (DT the) (CD two) (JJ nucleotide) (NNS chains)) (VP (VB wrap) (PRT (RP around)) (NP (DT the) (JJ same) (NNS axis)))))) (. .)))