( ( ( A ( narrow spot ) ) ( in ( the ( geyser ( tube ( or ( plumbing system ) ) ) ) ) ) ) ( ( ( ( makes ( it ( difficult ( for ( ( the water ) ( to flow ) ) ) ) ) ) , ) ( ( causing heat ) ( to ( build up ) ) ) ) . ) )
(ROOT (S (NP (NP (DT A) (JJ narrow) (NN spot)) (PP (IN in) (NP (DT the) (NN geyser) (NN tube) (CC or) (NN plumbing) (NN system)))) (VP (VBZ makes) (S (NP (PRP it)) (ADJP (JJ difficult) (PP (IN for) (NP (NP (DT the) (NN water)) (PP (TO to) (NP (NN flow))))))) (, ,) (S (VP (VBG causing) (NP (NN heat)) (S (VP (TO to) (VP (VB build) (PRT (RP up)))))))) (. .)))
A narrow spot in the geyser tube or plumbing system makes it difficult for the water to flow, causing heat to build up.
(ROOT (S (SBAR (WHADVP (WRB When)) (S (NP (NN water)) (VP (VP (VBZ is) (VP (VP (VBN heated) (PP (IN by) (NP (NN magma)))) (CC and) (VP (VBZ makes) (NP (PRP$ its) (NN way)) (PP (TO to) (NP (DT the) (NN surface)))))) (CC and) (VP (VBZ creates))))) (NP (DT a) (-LRB- -LRB-) (NN n) (-RRB- -RRB-)) (VP (VBP geyser)) (. .)))