( ( ( The ( irregular ( empty spaces ) ) ) ( between ( ( ( the putamen ) and ) ( the ( caudate nucleus ) ) ) ) ) ( ( were ( occupied ( by ( ( fiber bundles ) ( of ( the ( internal capsule ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (JJ irregular) (JJ empty) (NNS spaces)) (PP (IN between) (NP (NP (DT the) (NN putamen)) (CC and) (NP (DT the) (JJ caudate) (NN nucleus))))) (VP (VBD were) (ADJP (VBN occupied) (PP (IN by) (NP (NP (NN fiber) (NNS bundles)) (PP (IN of) (NP (DT the) (JJ internal) (NN capsule))))))) (. .)))
The irregular empty spaces between the putamen and the caudate nucleus were occupied by fiber bundles of the internal capsule.
(ROOT (S (NP (DT The) (NN nucleus)) (VP (VBZ is) (VP (VBN comprised) (ADVP (RB primarily)) (PP (IN of) (NP (JJ empty) (NN space))))) (. .)))