( ( ( ( The brain ) and ) ( spinal cord ) ) ( ( are ( covered ( by ( ( ( the meninges ) , ) ( ( the ( three ( protective membranes ) ) ) ( of ( ( ( ( ( the ( tough ( dura mater ) ) ) , ) ( the ( arachnoid mater ) ) ) and ) ( the ( pia mater ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN brain)) (CC and) (NP (JJ spinal) (NN cord))) (VP (VBP are) (VP (VBN covered) (PP (IN by) (NP (NP (DT the) (NNS meninges)) (, ,) (NP (NP (DT the) (CD three) (JJ protective) (NNS membranes)) (PP (IN of) (NP (NP (DT the) (JJ tough) (NN dura) (NN mater)) (, ,) (NP (DT the) (JJ arachnoid) (NN mater)) (CC and) (NP (DT the) (NN pia) (NN mater))))))))) (. .)))
The brain and spinal cord are covered by the meninges, the three protective membranes of the tough dura mater, the arachnoid mater and the pia mater.
(ROOT (S (NP (NP (DT The) (CD three) (NNS layers)) (PP (IN of) (NP (NP (JJ protective) (NNS coverings)) (PP (IN of) (NP (DT the) (JJ spinal) (NN cord)))))) (VP (VBZ is) (VP (VBN called) (NP (DT the) (NNS meninges)))) (. .)))