( ( Areas ( of concentration ) ) ( ( are ( described below ) ) . ) )
(ROOT (S (NP (NP (NNS Areas)) (PP (IN of) (NP (NN concentration)))) (VP (VBP are) (VP (VBN described) (ADVP (RB below)))) (. .)))
Areas of concentration are described below.
(ROOT (S (NP (DT The) (NN term) (NN concentration)) (VP (VBZ describes) (NP (NP (DT the) (NN number)) (PP (IN of) (NP (NP (NNS items)) (PP (IN in) (NP (NP (DT a) (VBN given) (NN area)) (CC or) (NP (NN volume)))))))) (. .)))