( This ( ( is ( ( ( ( the ( Global ( Positioning System ) ) ) ( -LRB- ( GPS -RRB- ) ) ) , ) ( which ( uses ( ( a fleet ) ( of ( ( 24 satellites ) ( ( carrying ( ( extremely accurate ) clocks ) ) ( to ( ( aid navigation ) worldwide ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT This)) (VP (VBZ is) (NP (NP (NP (DT the) (NNP Global) (NNP Positioning) (NNP System)) (PRN (-LRB- -LRB-) (NP (NNP GPS)) (-RRB- -RRB-))) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ uses) (NP (NP (DT a) (NN fleet)) (PP (IN of) (NP (NP (CD 24) (NNS satellites)) (VP (VBG carrying) (NP (ADJP (RB extremely) (JJ accurate)) (NNS clocks)) (S (VP (TO to) (VP (VB aid) (NP (NN navigation)) (ADVP (RB worldwide)))))))))))))) (. .)))
This is the Global Positioning System (GPS), which uses a fleet of 24 satellites carrying extremely accurate clocks to aid navigation worldwide.
(ROOT (S (S (NP (PRP We)) (VP (VBP call) (NP (NP (DT the) (JJ worldwide) (JJ radio-navigation) (NN system)) (VP (VBN formed) (PP (IN from) (NP (NP (DT a) (NN constellation)) (PP (IN of) (NP (CD 24) (NNS satellites))))))))) (CC and) (S (NP (PRP$ their) (NN ground) (NNS stations)) (VP (VBP gps))) (. .)))