( 12.1.2 ( ( ( Describe ( ( the effects ) ( of ( primary ( air pollution ) ) ) ) ) ( on health ) ) . ) )
(ROOT (S (NP (CD 12.1.2)) (VP (VBD Describe) (NP (NP (DT the) (NNS effects)) (PP (IN of) (NP (JJ primary) (NN air) (NN pollution)))) (PP (IN on) (NP (NN health)))) (. .)))
12.1.2 Describe the effects of primary air pollution on health.
(ROOT (S (NP (JJ Primary) (NNS pollutants)) (VP (VBP enter) (NP (DT the) (NN air)) (ADVP (RB directly))) (. .)))