( ( nitrogen-fixing bacteria ) ( living ( in ( the soil ) ) ) )
(ROOT (NP (NP (JJ nitrogen-fixing) (NNS bacteria)) (NP (NP (NN living)) (PP (IN in) (NP (DT the) (NN soil))))))
nitrogen-fixing bacteria living in the soil
(ROOT (S (NP (DT The) (NN nitrogen) (NN cycle)) (VP (VBZ includes) (NP (NP (NN air)) (, ,) (NP (NN soil)) (, ,) (CC and) (NP (VBG living) (NNS things)))) (. .)))