( ( Most ( of ( ( the activity ) ( in ( ( the cerebrum ) ( of ( the ( human brain ) ) ) ) ) ) ) ) ( ( is ( centered ( in ( ( a ( ( thin convoluted ) ( surface layer ) ) ) ( ( only ( a ( few mm ) ) ) thick ) ) ) ) ) . ) )
(ROOT (S (NP (NP (JJS Most)) (PP (IN of) (NP (NP (DT the) (NN activity)) (PP (IN in) (NP (NP (DT the) (NN cerebrum)) (PP (IN of) (NP (DT the) (JJ human) (NN brain)))))))) (VP (VBZ is) (VP (VBN centered) (PP (IN in) (NP (NP (DT a) (ADJP (JJ thin) (JJ convoluted)) (NN surface) (NN layer)) (ADJP (NP (RB only) (DT a) (JJ few) (NN mm)) (JJ thick)))))) (. .)))
Most of the activity in the cerebrum of the human brain is centered in a thin convoluted surface layer only a few mm thick.
(ROOT (S (NP (NP (DT The) (JJ iconic) (JJ gray) (NN mantle)) (PP (IN of) (NP (DT the) (JJ human) (NN brain))) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ appears) (S (VP (TO to) (VP (VB make) (PRT (RP up)) (NP (NP (JJS most)) (PP (IN of) (NP (NP (DT the) (NN mass)) (PP (IN of) (NP (DT the) (NN brain)))))))))))) (, ,)) (VP (VBZ is) (VP (VBN called) (NP (DT the) (NN cerebrum)))) (. .)))