( ( Imagine bubbles ) ( ( are ( ( coming ( to ( ( the surface ) ( of ( ( some water ) ( from ( ( a ( gas pipe ) ) ( with ( ( a ( leaky hole ) ) ( in it ) ) ) ) ) ) ) ) ) ) ( below ( that water ) ) ) ) . ) )
(ROOT (S (NP (JJ Imagine) (NNS bubbles)) (VP (VBP are) (VP (VBG coming) (PP (TO to) (NP (NP (DT the) (NN surface)) (PP (IN of) (NP (NP (DT some) (NN water)) (PP (IN from) (NP (NP (DT a) (NN gas) (NN pipe)) (PP (IN with) (NP (NP (DT a) (ADJP (JJ leaky)) (NN hole)) (PP (IN in) (NP (PRP it))))))))))) (PP (IN below) (NP (DT that) (NN water))))) (. .)))
Imagine bubbles are coming to the surface of some water from a gas pipe with a leaky hole in it below that water.
(ROOT (S (NP (NNP Gas) (NN bubble) (NNS holes)) (VP (VBZ helps) (NP (NP (JJ pumice) (NN float)) (PP (IN in) (NP (NN water))))) (. .)))