( ( The cranium ) ( ( is ( ( the skull ) ( that ( completely ( ( ( contains and ) protects ) ( the brain ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN cranium)) (VP (VBZ is) (NP (NP (DT the) (NN skull)) (SBAR (WHNP (WDT that)) (S (ADVP (RB completely)) (VP (VBZ contains) (CC and) (VBZ protects) (NP (DT the) (NN brain))))))) (. .)))
The cranium is the skull that completely contains and protects the brain.
(ROOT (S (NP (NP (DT The) (NN cranium)) (PRN (-LRB- -LRB-) (NP (NN skull)) (-RRB- -RRB-))) (VP (VBP protect) (S (-LRB- -LRB-) (NP (PRP s)) (-RRB- -RRB-) (NP (DT the) (NN brain)))) (. .)))
The cranium (skull) protect(s) the brain.