( OK ( I ( ( think ( we ( ( are all ) ( realizing ( ( ( that ( ( the ( carbon-carbon ( triple ( > bond ) ) ) ) ( consists ( of ( ( ( 1 ( sigma bond ) ) and ) ( 2 ( pi bonds ) ) ) ) ) ) ) and ) ( that ( ( a ( carbon-carbon ( > ( double bond ) ) ) ) ( ( is not ) ( free ( to rotate ) ) ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (ADVP (UH OK)) (NP (PRP I)) (VP (VBP think) (SBAR (S (NP (PRP we)) (VP (VBP are) (RB all) (VP (VBG realizing) (SBAR (SBAR (IN that) (S (NP (DT the) (JJ carbon-carbon) (JJ triple) (NN >) (NN bond)) (VP (VBZ consists) (PP (IN of) (NP (NP (CD 1) (NN sigma) (NN bond)) (CC and) (NP (CD 2) (NN pi) (NNS bonds))))))) (CC and) (SBAR (IN that) (S (NP (DT a) (JJ carbon-carbon) (JJ >) (JJ double) (NN bond)) (VP (VBZ is) (RB not) (ADJP (JJ free) (S (VP (TO to) (VP (VB rotate)))))))))))))) (. .)))
OK I think we are all realizing that the carbon-carbon triple &gt; bond consists of 1 sigma bond and 2 pi bonds and that a carbon-carbon &gt; double bond is not free to rotate.
(ROOT (S (NP (DT A) (JJ double) (NN bond)) (VP (VBZ consists) (PP (IN of) (NP (NP (CD one) (NN sigma) (NN bond)) (CC and) (NP (CD one) (NN pi) (NN bond))))) (. .)))