( ( Socially accepted ) ( , ( ( ( ( ( ( legal ( psychoactive substances ) ) ( -LRB- ( ( alcohol ( , ( nicotine ( , caffeine ) ) ) ) -RRB- ) ) ) , ) ( on ( the ( other hand ) ) ) ) , ) ( ( ( are not ) ( qualify ( as ( drugs ( for ( ( the aims ) ( of ( the ( following analysis ) ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (S (VP (ADVP (RB Socially)) (VBN accepted))) (, ,) (NP (NP (JJ legal) (NN psychoactive) (NNS substances)) (PRN (-LRB- -LRB-) (NP (NN alcohol) (, ,) (NN nicotine) (, ,) (NN caffeine)) (-RRB- -RRB-)) (, ,) (PP (IN on) (NP (DT the) (JJ other) (NN hand))) (, ,)) (VP (VBP are) (RB not) (VP (VB qualify) (PP (IN as) (NP (NP (NNS drugs)) (PP (IN for) (NP (NP (DT the) (NNS aims)) (PP (IN of) (NP (DT the) (JJ following) (NN analysis))))))))) (. .)))
Socially accepted, legal psychoactive substances (alcohol, nicotine, caffeine), on the other hand, are not qualify as drugs for the aims of the following analysis.
(ROOT (S (NP (NN Caffeine) (CC and) (NN alcohol)) (VP (VBP are) (NP (NP (CD two) (NNS examples)) (PP (IN of) (NP (DT a) (NN psychoactive))))) (. .)))
Caffeine and alcohol are two examples of a psychoactive.