to end on a positive ( if tragic ) note 
(ROOT (S (VP (TO to) (VP (VB end) (PP (IN on) (NP (DT a) (ADJP (JJ positive) (-LRB- -LRB-) (SBAR (IN if) (FRAG (ADJP (JJ tragic)))) (-RRB- -RRB-)) (NN note)))))))
(ROOT (S (VP (TO ) (VP (VB ) (PP (IN ) (NP (DT ) (ADJP (JJ ) (-LRB- ) (SBAR (IN ) (FRAG (ADJP (JJ )))) (-RRB- )) (NN )))))))