( ( Scuba diving ) ( ( is ( ( the process ) ( of ( ( observing and ) ( ( enjoying ( ( the ( underwater world ) ) ( for ( ( extended periods ) ( of time ) ) ) ) ) ( by ( using ( ( ( air tanks ) and ) ( special ( breathing apparatus ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Scuba) (NNP diving)) (VP (VBZ is) (NP (NP (DT the) (NN process)) (PP (IN of) (S (VP (VP (VBG observing)) (CC and) (VP (VBG enjoying) (NP (NP (DT the) (JJ underwater) (NN world)) (PP (IN for) (NP (NP (JJ extended) (NNS periods)) (PP (IN of) (NP (NN time)))))) (PP (IN by) (S (VP (VBG using) (NP (NP (NN air) (NNS tanks)) (CC and) (NP (JJ special) (NN breathing) (NN apparatus)))))))))))) (. .)))
Scuba diving is the process of observing and enjoying the underwater world for extended periods of time by using air tanks and special breathing apparatus.
(ROOT (S (NP (DT An) (JJ underwater) (NN spider)) (VP (VBZ uses) (NP (JJ shiny) (NN air) (NN bubble) (S (VP (TO to) (VP (VP (VB breathe)) (CC and) (VP (VB keep) (ADJP (JJ alive)))))))) (. .)))