( ( ( Hydrogen bonds ) ( If ( hydrogen ( is ( ( joined ( to ( any ( of ( ( ( the ( three ( most ( electronegative elements ) ) ) ) , ) ( fluorine ( , ( ( oxygen or ) nitrogen ) ) ) ) ) ) ) ) ( by ( a ( covalent bond ) ) ) ) ) ) ) ) ( , ( ( the bond ) ( ( is polar ) . ) ) ) )
(ROOT (S (SBAR (NP (CD Hydrogen) (NNS bonds)) (IN If) (S (NP (NN hydrogen)) (VP (VBZ is) (VP (VBN joined) (PP (TO to) (NP (NP (DT any)) (PP (IN of) (NP (NP (DT the) (CD three) (JJS most) (JJ electronegative) (NNS elements)) (, ,) (NP (NN fluorine) (, ,) (NN oxygen) (CC or) (NN nitrogen)))))) (PP (IN by) (NP (DT a) (JJ covalent) (NN bond))))))) (, ,) (NP (DT the) (NN bond)) (VP (VBZ is) (ADJP (JJ polar))) (. .)))
Hydrogen bonds If hydrogen is joined to any of the three most electronegative elements, fluorine, oxygen or nitrogen by a covalent bond , the bond is polar.
(ROOT (S (NP (NNP Oxygen)) (VP (VBZ is) (NP (NP (DT the) (NN name)) (PP (IN of) (NP (DT the) (JJ second) (ADJP (RBS most) (JJ electronegative)) (NN element))))) (. .)))