( ( ( Most tumors ) ( that ( spread ( to ( the brain ) ) ) ) ) ( ( ( ( ( do so ) ( via ( the ( blood stream ) ) ) ) and ) ( lodge ( between ( the ( ( ( gray and ) white ) matter ) ) ) ) ) . ) )
(ROOT (S (NP (NP (JJS Most) (NNS tumors)) (SBAR (WHNP (WDT that)) (S (VP (VBN spread) (PP (TO to) (NP (DT the) (NN brain))))))) (VP (VP (VBP do) (ADVP (RB so)) (PP (IN via) (NP (DT the) (NN blood) (NN stream)))) (CC and) (VP (VB lodge) (PP (IN between) (NP (DT the) (ADJP (JJ gray) (CC and) (JJ white)) (NN matter))))) (. .)))
Most tumors that spread to the brain do so via the blood stream and lodge between the gray and white matter.
(ROOT (S (NP (NP (JJS Most)) (PP (IN of) (NP (DT the) (JJ gray) (NN matter)))) (VP (VBZ is) (PP (IN on) (NP (NP (DT the) (NN surface)) (PP (IN of) (NP (DT the) (NN brain))))) (, ,) (S (VP (VBG surrounding) (NP (JJ white) (NN matter))))) (. .)))