Inflation is supposed to be a deadly poison, not a useful medicine.
( Inflation ( ( is ( supposed ( to ( be ( ( ( ( a ( deadly poison ) ) , ) not ) ( a ( useful medicine ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NN Inflation)) (VP (VBZ is) (VP (VBN supposed) (S (VP (TO to) (VP (VB be) (NP (NP (DT a) (JJ deadly) (NN poison)) (, ,) (RB not) (NP (DT a) (JJ useful) (NN medicine)))))))) (. .)))
Inflation is supposed to be poison, but economists are considering whether it might actually be useful.
( ( ( ( ( Inflation ( is ( supposed ( to ( be poison ) ) ) ) ) , ) but ) ( economists ( are ( considering ( whether ( it ( ( might actually ) ( be useful ) ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (NN Inflation)) (VP (VBZ is) (VP (VBN supposed) (S (VP (TO to) (VP (VB be) (NP (NN poison)))))))) (, ,) (CC but) (S (NP (NNS economists)) (VP (VBP are) (VP (VBG considering) (SBAR (IN whether) (S (NP (PRP it)) (VP (MD might) (ADVP (RB actually)) (VP (VB be) (ADJP (JJ useful))))))))) (. .)))